Transmission method, transmission device, reception method, and reception device

ABSTRACT

Provided is a transmission method that improves data reception quality in radio transmission using a single-carrier scheme and/or a multi-carrier scheme. The transmission method includes: generating a plurality of first modulated signals and a plurality of second modulated signals from transmission data, the plurality of first modulated signals being signals generated using a 16QAM modulation scheme, and the plurality of second modulated signals being signals generated using uniform constellation 64QAM modulation; generating, from the plurality of first modulated signals and the plurality of second modulated signals, a plurality of first signal-processed signals and a plurality of second signal-processed signals which satisfy a predetermined equation; and changing the predetermined equation when a 64QAM modulation used to generate the plurality of second modulated signals is switched from the uniform constellation 64QAM modulation to a non-uniform constellation 64QAM modulation.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/573,458, filed Sep. 17, 2019, which is a continuation of U.S. patentapplication Ser. No. 16/245,546, filed Jan. 11, 2019, which issued asU.S. Pat. No. 10,461,984 on Oct. 29, 2019, which is a U.S. continuationapplication of PCT International Patent Application NumberPCT/JP2017/025349 filed on Jul. 12, 2017, claiming the benefit ofpriority of U.S. Provisional Application No. 62/362,368 filed on Jul.14, 2016, and U.S. Provisional Application No. 62/523,036 filed on Jun.21, 2017, the entire contents of which are hereby incorporated byreference.

BACKGROUND 1. Technical Field

The present disclosure relates to a transmission method, a transmissiondevice, a reception method, and a reception device.

2. Description of the Related Art

As radio communications schemes, single-carrier schemes andmulti-carrier schemes such as OFDM (orthogonal frequency divisionmultiplexing) (for example, see J. A. C. Bingham, “MulticarrierModulation for Data Transmission: An Idea Whose Time Has Come”, IEEECommunications Magazine, May 1990) have been proposed. Multi-carrierschemes are advantageous in that they provide a high frequency-usageefficiency and are suitable for large-capacity transmission.Single-carrier schemes are advantageous in that they do not requiresignal processing such as FFT (fast Fourier transform) or IFFT (inverseFFT), and are thus suitable for realizing a low power consumptionimplementation.

SUMMARY

In radio communication using a single-carrier scheme and/ormulti-carrier scheme, a technique for improving data reception qualityis desired.

A transmission method according to one aspect of the present disclosureincludes a mapping step, a signal processing step, and a transmissionstep. In the mapping step, a plurality of first modulated signals s1(i)and a plurality of second modulated signals s2(i) are generated fromtransmission data, where i is a symbol number that is an integer greaterthan or equal to 0, the plurality of first modulated signals s1(i) aresignals generated using a 16QAM modulation scheme, and the plurality ofsecond modulated signals s2(i) are signals generated using uniformconstellation 64QAM modulation. In the signal processing step, aplurality of first signal-processed signals z1(i) and a plurality ofsecond signal-processed signals z2(i) that satisfy a predeterminedequation are generated from the plurality of first modulated signalss1(i) and the plurality of second modulated signals s2(i). In thetransmission step, the plurality of first signal-processed signals z1(i)and the plurality of second signal-processed signals z2(i) aretransmitted using a plurality of antennas. Among the plurality of firstsignal-processed signals z1(i) and the plurality of secondsignal-processed signals z2(i), a first signal-processed signal and asecond signal-processed signal that have identical symbol numbers aresimultaneously transmitted at the same frequency. Here, when the 64QAMmodulation used to generate the plurality of second modulated signalss2(i) is switched from the uniform constellation 64QAM modulation to anon-uniform constellation 64QAM modulation, the predetermined equationis changed.

A transmission device according to one aspect of the present disclosureincludes a mapper, a signal processor, and a transmitter. The mappergenerates a plurality of first modulated signals s1(i) and a pluralityof second modulated signals s2(i) from transmission data, where i is asymbol number that is an integer greater than or equal to 0, theplurality of first modulated signals s1(i) are signals generated using a16QAM modulation scheme, and the plurality of second modulated signalss2(i) are signals generated using uniform constellation 64QAMmodulation. The signal processor generates a plurality of firstsignal-processed signals z1(i) and a plurality of secondsignal-processed signals z2(i) that satisfy a predetermined equationfrom the plurality of first modulated signals s1(i) and the plurality ofsecond modulated signals s2(i). The transmitter transmits the pluralityof first signal-processed signals z1(i) and the plurality of secondsignal-processed signals z2(i) using a plurality of antennas. Among theplurality of first signal-processed signals z1(i) and the plurality ofsecond signal-processed signals z2(i), a first signal-processed signaland a second signal-processed signal that have identical symbol numbersare simultaneously transmitted at the same frequency. Here, when the64QAM modulation used to generate the plurality of second modulatedsignals s2(i) is switched from the uniform constellation 64QAMmodulation to a non-uniform constellation 64QAM modulation, the signalprocessor changes the predetermined equation.

A reception method according to one aspect of the present disclosureincludes a reception step and a demodulation step. In the receptionstep, reception signals are obtained by receiving a first transmissionsignal and a second transmission signal transmitted from differentantennas. The first transmission signal and the second transmissionsignal are signals resulting from transmitting a plurality of firstsignal-processed signals z1(i) and a plurality of secondsignal-processed signals z2(i) using a plurality of antennas, where i isa symbol number that is an integer greater than or equal to 0, and amongthe plurality of first signal-processed signals z1(i) and the pluralityof second signal-processed signals z2(i), a first signal-processedsignal and a second signal-processed signal that have identical symbolnumbers are simultaneously transmitted at the same frequency. Theplurality of first signal-processed signals z1(i) and the plurality ofsecond signal-processed signals z2(i) are signals generated byperforming first signal processing and second signal processing on aplurality of first modulated signals s1(i) generated using a 16QAMmodulation scheme and a plurality of second modulated signals s2(i)generated using uniform constellation 64QAM modulation. The plurality offirst signal-processed signals z1(i) and the plurality of secondsignal-processed signals z2(i) satisfy a predetermined equation inregard to the plurality of first modulated signals s1(i) and theplurality of second modulated signals s2(i). In the demodulation step,the reception signals are demodulated by performing signal processingcorresponding to the first signal processing and the second signalprocessing. Here, when the 64QAM modulation used to generate theplurality of second modulated signals s2(i) is switched from the uniformconstellation 64QAM modulation to a non-uniform constellation 64QAMmodulation, the predetermined equation is changed.

A reception device according to one aspect of the present disclosureincludes a receiver and a demodulator. The receiver obtains receptionsignals by receiving a first transmission signal and a secondtransmission signal transmitted from different antennas. The firsttransmission signal and the second transmission signal are signalsresulting from transmitting a plurality of first signal-processedsignals z1(i) and a plurality of second signal-processed signals z2(i)using a plurality of antennas, where i is a symbol number that is aninteger greater than or equal to 0, and among the plurality of firstsignal-processed signals z1(i) and the plurality of secondsignal-processed signals z2(i), a first signal-processed signal and asecond signal-processed signal that have identical symbol numbers aresimultaneously transmitted at the same frequency. The plurality of firstsignal-processed signals z1(i) and the plurality of secondsignal-processed signals z2(i) are signals generated by performing firstsignal processing and second signal processing on a plurality of firstmodulated signals s1(i) generated using a 16QAM modulation scheme and aplurality of second modulated signals s2(i) generated using uniformconstellation 64QAM modulation. The plurality of first signal-processedsignals z1(i) and the plurality of second signal-processed signals z2(i)satisfy a predetermined equation in regard to the plurality of firstmodulated signals s1(i) and the plurality of second modulated signalss2(i). The demodulator demodulates the reception signals by performingsignal processing corresponding to the first signal processing and thesecond signal processing. Here, when the 64QAM modulation used togenerate the plurality of second modulated signals s2(i) is switchedfrom the uniform constellation 64QAM modulation to a non-uniformconstellation 64QAM modulation, the predetermined equation is changed.

According to the present disclosure, it is possible to improve datareception quality is desired in radio communication using asingle-carrier scheme and/or multi-carrier scheme.

BRIEF DESCRIPTION OF DRAWINGS

These and other objects, advantages and features of the disclosure willbecome apparent from the following description thereof taken inconjunction with the accompanying drawings that illustrate a specificembodiment of the present disclosure.

FIG. 1 illustrates one example of a configuration of a transmissiondevice;

FIG. 2 illustrates one example of a configuration of a signal processorin a transmission device;

FIG. 3 illustrates one example of a configuration of a signal processorin a transmission device;

FIG. 4 illustrates the capacity for each SNR in an AWGN environment;

FIG. 5 illustrates one example of a configuration of a radio unit in atransmission device;

FIG. 6 illustrates one example of a frame configuration of atransmission signal;

FIG. 7 illustrates one example of a frame configuration of atransmission signal;

FIG. 8 illustrates one example of a configuration of components relevantto control information generation;

FIG. 9 illustrates one example of a configuration of an antenna unit ina transmission device;

FIG. 10 illustrates one example of a frame configuration of atransmission signal;

FIG. 11 illustrates one example of a frame configuration of atransmission signal;

FIG. 12 illustrates one example of a symbol arrangement method withrespect to the time axis;

FIG. 13 illustrates one example of a symbol arrangement method withrespect to the frequency axis;

FIG. 14 illustrates one example of a symbol arrangement method withrespect to the time and frequency axes;

FIG. 15 illustrates one example of a symbol arrangement method withrespect to the time axis;

FIG. 16 illustrates one example of a symbol arrangement method withrespect to the frequency axis;

FIG. 17 illustrates one example of a symbol arrangement method withrespect to the time and frequency axes;

FIG. 18 illustrates one example of a configuration of a radio unit in atransmission device;

FIG. 19 illustrates one example of a configuration of a receptiondevice;

FIG. 20 illustrates one example of the relationship between atransmission device and a reception device;

FIG. 21 illustrates one example of a configuration of an antenna unit ina reception device;

FIG. 22 illustrates one example of a configuration of a transmissiondevice;

FIG. 23 illustrates one example of a configuration of a signal processorin a transmission device;

FIG. 24 illustrates one example of a configuration of a signal processorin a transmission device;

FIG. 25 illustrates one example of a configuration of a signal processorin a transmission device;

FIG. 26 illustrates one example of part of a configuration in a signalprocessor in a transmission device;

FIG. 27 illustrates one example of part of a configuration in a signalprocessor in a transmission device;

FIG. 28 illustrates one example of part of a configuration in a signalprocessor in a transmission device;

FIG. 29 illustrates one example of part of a configuration in a signalprocessor in a transmission device;

FIG. 30 illustrates one example of part of a configuration in a signalprocessor in a transmission device;

FIG. 31 illustrates a configuration when CDD is used; and

FIG. 32 illustrates, per SNR, the relationship between (i) the averagepower ratio for 16QAM relative to the sum of the average power for 16QAMand the average power for 64QAM and (ii) capacity.

DESCRIPTION OF THE EMBODIMENTS Embodiment 1

A transmission method, transmission device, reception method, andreception device according to this embodiment will be described indetail.

FIG. 1 illustrates one example of a configuration of a transmissiondevice according to this embodiment, such as a base station, accesspoint, or broadcast station. Error correction encoder 102 receivesinputs of data 101 and control signal 100, and based on informationrelated to the error correction code included in control signal 100(e.g., error correction code information, code length (block length),encode rate), performs error correction encoding, and outputs encodeddata 103. Note that error correction encoder 102 may include aninterleaver. In such a case, error correction encoder 102 may rearrangethe encoded data before outputting encoded data 103.

Mapper 104 receives inputs of encoded data 103 and control signal 100,and based on information on the modulated signal included in controlsignal 100, performs mapping in accordance with the modulation scheme,and outputs mapped signal (baseband signal) 105_1 and mapped signal(baseband signal) 105_2. Note that mapper 104 generates mapped signal105_1 using a first sequence and generates mapped signal 105_2 using asecond sequence. Here, the first sequence and second sequence aredifferent.

Signal processor 106 receives inputs of mapped signals 105_1 and 105_2,signal group 110, and control signal 100, performs signal processingbased on control signal 100, and outputs signal-processed signals 106_Aand 106_B. Here, signal-processed signal 106_A is expressed as u1(i),and signal-processed signal 106_B is expressed as u2(i) (i is a symbolnumber; for example, i is an integer that is greater than or equal to0). Note that details regarding the signal processing will be describedwith reference to FIG. 2 later.

Radio unit 107_A receives inputs of signal-processed signal 106_A andcontrol signal 100, and based on control signal 100, processessignal-processed signal 106_A and outputs transmission signal 108_A.Transmission signal 108_A is then output as radio waves from antennaunit #A (109_A).

Similarly, radio unit 107B receives inputs of signal-processed signal106_B and control signal 100, and based on control signal 100, processessignal-processed signal 106_B and outputs transmission signal 108_B.Transmission signal 108B is then output as radio waves from antenna unit#B (109_B).

Antenna unit #A (109_A) receives an input of control signal 100. Here,based on control signal 100, antenna unit #A (108_A) processestransmission signal 108_A and outputs the result as radio waves.However, antenna unit #A (109_A) may not receive an input of controlsignal 100.

Similarly, antenna unit #B (109_B) receives an input of control signal100. Here, based on control signal 100, antenna unit #B (108_B)processes transmission signal 108_B and outputs the result as radiowaves. However, antenna unit #B (109_B) may not receive an input ofcontrol signal 100.

Note that control signal 100 may be generated based on informationtransmitted by a device that is the communication partner in FIG. 1 ,and, alternatively, the device in FIG. 1 may include an input unit, andcontrol signal 100 may be generated based on information input from theinput unit.

FIG. 2 illustrates one example of a configuration of signal processor106 illustrated in FIG. 1 . Weighting synthesizer (precoder) 203receives inputs of mapped signal 201A (mapped signal 105_1 in FIG. 1 ),mapped signal 201B (mapped signal 105_2 in FIG. 1 ), and control signal200 (control signal 100 in FIG. 1 ), performs weighting synthesis(precoding) based on control signal 200, and outputs weighted signal204A and weighted signal 204B. Here, mapped signal 201A is expressed ass1(t), mapped signal 201B is expressed as s2(t), weighted signal 204A isexpressed as z1(t), and weighted signal 204B is expressed as z2′(t).Note that one example oft is time (s1(t), s2(t), z1(t), and z2′(t) aredefined as complex numbers (accordingly, they may be real numbers)).

Weighting synthesizer (precoder) 203 performs the following calculation.

$\begin{matrix}\lbrack {{MATH}.1} \rbrack & \end{matrix}$ $\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2^{\prime}(i)}\end{pmatrix} = {\begin{pmatrix}a & b \\c & d\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} & {{Equation}(1)}\end{matrix}$

In Equation (1), a, b, c, and d can be defined as complex numbers.Accordingly, a, b, c, and d are complex numbers (and may be realnumbers). Note that i is a symbol number.

Phase changer 205B receives inputs of weighting synthesized signal 204Band control signal 200, applies a phase change to weighting synthesizedsignal 204B based on control signal 200, and outputs phase-changedsignal 206B. Note that phase-changed signal 206B is expressed as z2(t),and z2(t) is defined as a complex number (and may be a real number).

Next, specific operations performed by phase changer 205B will bedescribed. In phase changer 205B, for example, a phase change of y(i) isapplied to z2′(i). Accordingly, z2(i) can be expressed asz2(i)=y(i)×z2′(i) (i is a symbol number (i is an integer that is greaterthan or equal to 0)).

For example, the phase change value is set as shown below (N is aninteger that is greater than or equal to 2, N is a phase changecycle)(when N is set to an odd number greater than or equal to 3, datareception quality may be improved).

$\begin{matrix}\lbrack {{MATH}.2} \rbrack & \end{matrix}$ $\begin{matrix}{{y(i)} = e^{j\frac{2 \times \pi \times i}{N}}} & {{Equation}(2)}\end{matrix}$

(j is an imaginary number unit). However, Equation (2) is merely anon-limiting example. Here, phase change value y(i)=ej×δ(i).

Here, z1(i) and z2(i) can be expressed with the following equation.

$\begin{matrix}\lbrack {{MATH}.3} \rbrack & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}a & b \\c & d\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}a & b \\c & d\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix} & {{Equation}(3)}\end{matrix}$

Note that δ(i) is a real number. z1(i) and z2(i) are transmitted fromthe transmission device at the same time and using the same frequency(same frequency band).

In Equation (3), the phase change value is not limited to the value usedin Equation (2); for example, a method in which the phase is changedcyclically or regularly is conceivable.

The matrix (precoding matrix) in Equation (1) and Equation (3) is asfollows.

$\begin{matrix}\lbrack {{MATH}.4} \rbrack & \end{matrix}$ $\begin{matrix}{\begin{pmatrix}a & b \\c & d\end{pmatrix} = F} & {{Equation}(4)}\end{matrix}$

For example, using the following matrix for matrix F is conceivable.

$\begin{matrix}\lbrack {{MATH}.5} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times e^{j0}} & {\beta \times \alpha \times e^{j0}} \\{\beta \times \alpha \times e^{j0}} & {\beta \times e^{j\pi}}\end{pmatrix}}{or}} & {{Equation}(5)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.6} \rbrack & \end{matrix}$ $\begin{matrix}{{F = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}e^{j0} & {\alpha \times e^{j0}} \\{\alpha \times e^{j0}} & e^{j\pi}\end{pmatrix}}}{or}} & {{Equation}(6)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.7} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times e^{j0}} & {\beta \times \alpha \times e^{j\pi}} \\{\beta \times \alpha \times e^{j0}} & {\beta \times e^{j0}}\end{pmatrix}}{or}} & {{Equation}(7)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.8} \rbrack & \end{matrix}$ $\begin{matrix}{{F = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}e^{j0} & {\alpha \times e^{j\pi}} \\{\alpha \times e^{j0}} & e^{j0}\end{pmatrix}}}{or}} & {{Equation}(8)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.9} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times \alpha \times e^{j0}} & {\beta \times e^{j\pi}} \\{\beta \times e^{j0}} & {\beta \times \alpha \times e^{j0}}\end{pmatrix}}{or}} & {{Equation}(9)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.{10}} \rbrack & \end{matrix}$ $\begin{matrix}{{F = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}{\alpha \times e^{j0}} & e^{j\pi} \\e^{j0} & {\alpha \times e^{j0}}\end{pmatrix}}}{or}} & {{Equation}(10)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.{11}} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times \alpha \times e^{j0}} & {\beta \times e^{j0}} \\{\beta \times e^{j0}} & {\beta \times \alpha \times e^{j\pi}}\end{pmatrix}}{or}} & {{Equation}(11)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.12} \rbrack & \end{matrix}$ $\begin{matrix}{F = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}{\alpha \times e^{j0}} & e^{j0} \\e^{j0} & {\alpha \times e^{j\pi}}\end{pmatrix}}} & {{Equation}(12)}\end{matrix}$

Note that in Equation (5), Equation (6), Equation (7), Equation (8),Equation (9), Equation (10), Equation (11), and Equation (12), α may bea real number and may be an imaginary number, and β may be a real numberand may be an imaginary number. However, α is not 0 (zero). β is alsonot 0 (zero).

or

$\begin{matrix}\lbrack {{MATH}.13} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}}{or}} & {{Equation}(13)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.14} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}}{or}} & {{Equation}(14)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.{15}} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}}{or}} & {{Equation}(15)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.16} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}}{or}} & {{Equation}(16)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.{17}} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times \sin\theta} & {{- \beta} \times \cos\theta} \\{\beta \times \cos\theta} & {\beta \times \sin\theta}\end{pmatrix}}{or}} & {{Equation}(17)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.18} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\sin\theta} & {{- \cos}\theta} \\{\cos\theta} & {\sin\theta}\end{pmatrix}}{or}} & {{Equation}(18)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.19} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times \sin\theta} & {\beta \times \cos\theta} \\{\beta \times \cos\theta} & {{- \beta} \times \sin\theta}\end{pmatrix}}{or}} & {{Equation}(19)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.20} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\sin\theta} & {\cos\theta} \\{\cos\theta} & {{- \sin}\theta}\end{pmatrix}}{or}} & {{Equation}(20)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.21} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = \begin{pmatrix}{\beta \times e^{j{\theta_{11}(i)}}} & {\beta \times \alpha \times e^{j{({{\theta_{11}(i)} + \lambda})}}} \\{\beta \times \alpha \times e^{j{\theta_{21}(i)}}} & {\beta \times e^{j{({{\theta_{21}(i)} + \lambda + \pi})}}}\end{pmatrix}}{or}} & {{Equation}(21)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.{22}} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}e^{j{\theta_{11}(i)}} & {\alpha \times e^{j{({{\theta_{11}(i)} + \lambda})}}} \\{\alpha \times e^{j{\theta_{21}(i)}}} & e^{j{({{\theta_{21}(i)} + \lambda + \pi})}}\end{pmatrix}}}{or}} & {{Equation}(22)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.23} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = \begin{pmatrix}{\beta \times \alpha \times e^{j{\theta_{21}(i)}}} & {\beta \times e^{j{({{\theta_{21}(i)} + \lambda + \pi})}}} \\{\beta \times e^{j{\theta_{11}(i)}}} & {\beta \times \alpha \times e^{j{({{\theta_{11}(i)} + \lambda})}}}\end{pmatrix}}{or}} & {{Equation}(23)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.24} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}{\alpha \times e^{j{\theta_{21}(i)}}} & e^{j{({{\theta_{21}(i)} + \lambda + \pi})}} \\e^{j{\theta_{11}(i)}} & {\alpha \times e^{j{({{\theta_{11}(i)} + \lambda})}}}\end{pmatrix}}}{or}} & {{Equation}(24)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.25} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = \begin{pmatrix}{\beta \times e^{j\theta_{11}}} & {\beta \times \alpha \times e^{j{({\theta_{11} + {\lambda(i)}})}}} \\{\beta \times \alpha \times e^{j\theta_{21}}} & {\beta \times e^{j{({\theta_{21} + {\lambda(i)} + \pi})}}}\end{pmatrix}}{or}} & {{Equation}(25)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.26} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}e^{j\theta_{11}} & {\alpha \times e^{j{({\theta_{11} + {\lambda(i)}})}}} \\{\alpha \times e^{j\theta_{21}}} & e^{j{({\theta_{21} + {\lambda(i)} + \pi})}}\end{pmatrix}}}{or}} & {{Equation}(26)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.27} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = \begin{pmatrix}{\beta \times \alpha \times e^{j\theta_{21}}} & {\beta \times e^{j{({\theta_{21} + {\lambda(i)} + \pi})}}} \\{\beta \times e^{j\theta_{11}}} & {\beta \times \alpha \times e^{j{({\theta_{11} + {\lambda(i)}})}}}\end{pmatrix}}{or}} & {{Equation}(27)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.28} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}{\alpha \times e^{j\theta_{21}}} & e^{j{({\theta_{21} + {\lambda(i)} + \pi})}} \\e^{j\theta_{11}} & {\alpha \times e^{j{({\theta_{11} + {\lambda(i)}})}}}\end{pmatrix}}}{or}} & {{Equation}(28)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.29} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times e^{j\theta_{11}}} & {\beta \times \alpha \times e^{j{({\theta_{11} + \lambda})}}} \\{\beta \times \alpha \times e^{j\theta_{21}}} & {\beta \times e^{j{({\theta_{21} + \lambda + \pi})}}}\end{pmatrix}}{or}} & {{Equation}(29)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.30} \rbrack & \end{matrix}$ $\begin{matrix}{{F = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}e^{j\theta_{11}} & {\alpha \times e^{j{({\theta_{11} + \lambda})}}} \\{\alpha \times e^{j\theta_{21}}} & e^{j{({\theta_{21} + \lambda + \pi})}}\end{pmatrix}}}{or}} & {{Equation}(30)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.31} \rbrack & \end{matrix}$ $\begin{matrix}{{F = \begin{pmatrix}{\beta \times \alpha \times e^{j\theta_{21}}} & {\beta \times e^{j{({\theta_{21} + \lambda + \pi})}}} \\{\beta \times e^{j\theta_{11}}} & {\beta \times \alpha \times e^{j{({\theta_{11} + \lambda})}}}\end{pmatrix}}{or}} & {{Equation}(31)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.32} \rbrack & \end{matrix}$ $\begin{matrix}{F = {\frac{1}{\sqrt{\alpha^{2} + 1}}\begin{pmatrix}{\alpha \times e^{j\theta_{21}}} & e^{j{({\theta_{21} + \lambda + \pi})}} \\e^{j\theta_{11}} & {\alpha \times e^{j{({\theta_{11} + \lambda})}}}\end{pmatrix}}} & {{Equation}(32)}\end{matrix}$

However, θ₁₁(i), θ₂₁(i), and λ(i) are functions (real numbers) of i(symbol number). λ is, for example, a fixed value (real number)(however, λ need not be a fixed value). α may be a real number, and,alternatively, may be an imaginary number. β may be a real number, and,alternatively, may be an imaginary number. However, α is not 0 (zero). βis also not 0 (zero). Moreover, θ11 and θ21 are real numbers.

Moreover, each exemplary embodiment herein can also be carried out byusing a precoding matrix other than these matrices.

or

$\begin{matrix}\lbrack {{MATH}.33} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = \begin{pmatrix}1 & 0 \\0 & 1\end{pmatrix}}{or}} & {{Equation}(33)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.34} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = \begin{pmatrix}\beta & 0 \\0 & \beta\end{pmatrix}}{or}} & {{Equation}(34)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.35} \rbrack & \end{matrix}$ $\begin{matrix}{{{F(i)} = \begin{pmatrix}1 & 0 \\0 & {- 1}\end{pmatrix}}{or}} & {{Equation}(35)}\end{matrix}$ $\begin{matrix}\lbrack {{MATH}.36} \rbrack & \end{matrix}$ $\begin{matrix}{{F(i)} = \begin{pmatrix}\beta & 0 \\0 & {- \beta}\end{pmatrix}} & {{Equation}(36)}\end{matrix}$

Note that in Equation (34) and Equation (36), β may be a real numberand, alternatively, may be an imaginary number. However, β is not 0(zero). When the precoding matrix is expressed as in Equation (33) andEquation (34), weighting synthesizer 203 in FIG. 2 outputs mapped signal201A as weighting synthesized signal 204A and mapped signal 201B asweighting synthesized signal 204B without performing signal processingon mapped signals 201A, 201B. Stated differently, weighting synthesizer203 may be omitted. Alternately, when weighting synthesizer 203 isprovided, control for whether to perform weighting synthesis or not maybe determined according to control signal 200.

Inserter 207A receives inputs of weighting synthesized signal 204A,pilot symbol signal (pa(t))(t is time)(251A), preamble signal 252,control information symbol signal 253, and control signal 200, and basedon information on the frame configuration included in control signal200, outputs baseband signal 208A based on the frame configuration.

Similarly, inserter 207B receives inputs of phase-changed signal 206B,pilot symbol signal (pb(t)) (t: time) (251B), preamble signal 252,control information symbol signal 253, and control signal 200, and basedon information on the frame configuration included in control signal200, outputs baseband signal 208B based on the frame configuration.

Phase changer 209B receives inputs of baseband signal 208B and controlsignal 200, applies a phase change to baseband signal 208B based oncontrol signal 200, and outputs phase-changed signal 210B. Basebandsignal 208B is a function of symbol number i (i is an integer that isgreater than or equal to 0), and is expressed as x′(i). Then,phase-changed signal 210B (x(i)) can be expressed as x(i)=ej×ε(i)×x′(i)(j is an imaginary number unit).

Note that the operation performed by phase changer 209B may be CDD(cyclic delay diversity) or CSD (cycle shift diversity) disclosed inNPTL 2 and 3. One characteristic of phase changer 209B is that itapplies a phase change to a symbol present along the frequency axis(i.e., applies a phase change to, for example, a data symbol, a pilotsymbol, and/or a control information symbol).

In FIG. 2 , phase changer 209B is included in the configuration, butphase changer 209B may be omitted from the configuration. In such cases,baseband signals 208A, 208B are the output in FIG. 2 (phase changer 209Bneed not operate).

FIG. 3 illustrates an example of a configuration of signal processor 106illustrated in FIG. 1 that differs from the configuration illustrated inFIG. 2 . In FIG. 3 , components that operate the same as in FIG. 2 sharelike reference marks. Note that duplicate description of components thatperform the same operations as in FIG. 2 will be omitted.

Coefficient multiplier 301A receives inputs of mapped signal 201A(s1(i)) and control signal 200, and based on control signal 200,multiplies mapped signal 201A (s1(i)) by a coefficient, and outputscoefficient multiplied signal 302A. Note that when the coefficient isexpressed as u, coefficient multiplied signal 302A is expressed asu×s1(i) (u may be a real number and, alternatively, may be a complexnumber). However, when u=1, coefficient multiplier 301A outputs mappedsignal 201A (s1(i)) as coefficient multiplied signal 302A withoutmultiplying mapped signal 201A (s1(i)) by the coefficient.

Similarly, coefficient multiplier 301B receives inputs of mapped signal201B (s2(i)) and control signal 200, and based on control signal 200,multiplies mapped signal 201B (s2(i)) by a coefficient, and outputscoefficient multiplied signal 302B. Note that when the coefficient isexpressed as v, coefficient multiplied signal 302B is expressed asv×s2(i) (v may be a real number and, alternatively, may be a complexnumber). However, when v=1, coefficient multiplier 301B outputs mappedsignal 201B (s2(i)) as coefficient multiplied signal 302B withoutmultiplying mapped signal 201B (s2(i)) by the coefficient.

Accordingly, weighting synthesized signal 204A (z1(i)) and phase-changedsignal 206B (z2(i)) can be expressed with the following equation.

$\begin{matrix}\lbrack {{MATH}.37} \rbrack & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}a & b \\c & d\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}a & b \\c & d\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix} & {{Equation}(37)}\end{matrix}$

Note that the example of the (precoding) matrix F is as previouslydescribed (for example, see Equation (5) through Equation (36)), and theexample of phase change value y(i) is as indicated in Equation (2), butthe (precoding) matrix F and phase change value y(i) are not limited tothese examples.

Next, “the (precoding) matrix F and phase change value y(i) when themodulation scheme for mapped signal 201A (s1(i)) is QPSK (quadraturephase shift keying) and the modulation scheme used for mapped signal201B (s2(i)) is 16QAM (QAM: quadrature amplitude modulation)” used inthe description of the present invention will be described.

Note that here, the average (transmission) power of mapped signal 201Aand the average (transmission) power of mapped signal 201B are the same.

In such cases, by obtaining weighting synthesized signal 204A (z1(i))and phase-changed signal 206B (z2(i)) as illustrated in Equation (38)through Equation (45), in the reception device that receives themodulated signal transmitted by the transmission device illustrated inFIG. 1 , an advantageous effect that data reception quality is improvedcan be achieved.

$\begin{matrix}{\lbrack {{MATH}.38} \rbrack} & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}\sqrt{\frac{2}{3}} & 0 \\0 & \sqrt{\frac{4}{3}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix} & {{Equation}(38)}\end{matrix}$ $\begin{matrix}{\lbrack {{MATH}.39} \rbrack} & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{4}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix} & {{Equation}(39)}\end{matrix}$ $\begin{matrix}{\lbrack {{MATH}.40} \rbrack} & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{3}} & 0 \\0 & \sqrt{\frac{4}{3}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix} & {{Equation}(40)}\end{matrix}$ $\begin{matrix}{\lbrack {{MATH}.41} \rbrack} & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{4}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix} & {{Equation}(41)}\end{matrix}$ $\begin{matrix}{\lbrack {{MATH}.42} \rbrack} & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}\sqrt{\frac{2}{3}} & 0 \\0 & \sqrt{\frac{4}{3}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix} & {{Equation}(42)}\end{matrix}$ $\begin{matrix}{\lbrack {{MATH}.43} \rbrack} & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{4}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix} & {{Equation}(43)}\end{matrix}$ $\begin{matrix}{\lbrack {{MATH}.44} \rbrack} & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{3}} & 0 \\0 & \sqrt{\frac{4}{3}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix} & {{Equation}(44)}\end{matrix}$ $\begin{matrix}{\lbrack {{MATH}.45} \rbrack} & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{4}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix} & {{Equation}(45)}\end{matrix}$

Note that in Equation (38) through Equation (45), α and β may be realnumbers and, alternatively, may be imaginary numbers.

Next, the characteristic points of Equation (38) through Equation (45)will be described.

In Equation (38) through Equation (45), θ is set to π/4 radians (45degrees). The average (transmission) power of coefficient multipliedsignal 302A and the average (transmission) power of coefficientmultiplied signal 302B are different, but by setting θ to π/4 radians(45 degrees), the average (transmission) power of weighting synthesizedsignal 204A (z1(i)) and the average (transmission) power ofphase-changed signal 206B (z2(i)) can be made to be the same, so whenthe transmission rules stipulate a condition that the averagetransmission power of each modulated signal transmitted from theantennas be the same, it is necessary to set θ to π/4 radians (45degrees). Note that, here, θ is set to π/4 radians (45 degrees), but 0may be set to any one of; π/4 radians (45 degrees); (3×π)/4 radians (135degrees); (5×π)/4 radians (225 degrees); and (7×π)/4 radians (315degrees).

Moreover, the coefficients u, v are set as illustrated in Equation (38)through Equation (45).

Note that symbols (for example, z1(i), z2(i)) are described as beinggenerated using the methods exemplified in FIG. 1 , FIG. 2 , FIG. 3 ,and Equation (1) through Equation (45). In such cases, the generatedsymbols may be arranged along the time axis. When a multi-carrier schemesuch as OFDM (orthogonal frequency division multiplexing) is used, thegenerated symbols may be arranged along the frequency axis and may bearranged along the time and frequency axes. Moreover, the generatedsymbols may be interleaved (i.e., rearranged) and arranged along thetime axis, along the frequency axis, and along the time and frequencyaxes. However, z1(i) and z2(i), which are both symbol number i, aretransmitted from the transmission device at the same time and using thesame frequency (same frequency band).

FIG. 4 shows the capacity for each SNR (signal-to-noise power ratio). InFIG. 4 , P_(QPSK)/(P_(QPSK)+P_(16QAM)) is represented on the horizontalaxis, and capacity is represented on the vertical axis. P_(QPSK) is theaverage (transmission) power of QPSK, and P_(16QAM) is the average(transmission) power of 16QAM (note that the channel model in the graphis an AWGN (additive white Gaussian noise) environment). As can be seenfrom the results, by using the settings illustrated in Equation (38)through Equation (45), the reception device can achieve an advantageouseffect of good data reception quality. Note that in FIG. 4 , the 21 linegraphs indicating relationships between power ratio and capacitycorrespond to, in ascending order of capacity, SNR=0 dB, 1 dB, 2 dB . .. 20 dB

The transmission device illustrated in FIG. 1 switches the transmissionmethod of the modulated signal based on information on the transmissionmethod included in control signal 100. The transmission deviceillustrated in FIG. 1 can select the following transmission methods.

Transmission Method #1:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (binary phase shift keying) (or π/2 shiftBPSK) (however, the single stream modulated signal may be transmittedusing a single antenna and, alternatively, transmitted using a pluralityof antennas).

Transmission Method #2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (quadrature phase shift keying) (or π/2 shiftQPSK) (however, the single stream modulated signal may be transmittedusing a single antenna and, alternatively, transmitted using a pluralityof antennas).

Transmission Method #3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is 16QAM (or π/2 shift 16QAM) (or a modulation schemein which 16 signal points are in the in-phase I-quadrature Q plane, suchas 16APSK (APSK: amplitude phase shift keying) (a shift may beperformed)) (however, the single stream modulated signal may betransmitted using a single antenna and, alternatively, transmitted usinga plurality of antennas).

Transmission Method #4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is 64QAM (or π/2 shift 64QAM) (or a modulation schemein which 64 signal points are in the in-phase I-quadrature Q plane, suchas 64APSK (APSK: amplitude phase shift keying) (a shift may beperformed)) (however, the single stream modulated signal may betransmitted using a single antenna and, alternatively, transmitted usinga plurality of antennas).

Transmission Method #5:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is BPSK (or π/2 shift BPSK), and themodulation scheme of s2(i) is BPSK (or π/2 shift BPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas.

Transmission Method #6:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is QPSK (or π/2 shift QPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas.

Transmission Method #7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas.

Transmission Method #8

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas.

Transmission Method #9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas.

Here, based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) and aphase change are performed (phase changer 205B need not perform a phasechange), and any one of the (precoding) matrices in Equation (13)through Equation (20) is used as the precoding matrix. However, θ inEquation (13) through Equation (20) is greater than or equal to 0radians and less than 2π radians (0 radians≤θ<2π radians).

With this, the following is satisfied.

Transmission Method #1:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #2:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #3:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #4:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Transmission Method #5:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 2 and less than or equalto 4. However, when θ=0 radians in Equation (13) through Equation (20),the number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #6:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 4 and less than or equalto 16. However, when θ=0 radians in Equation (13) through Equation (20),the number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #7:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 4 and less than or equalto 64. However, when θ=0 radians in Equation (13) through Equation (20),the number of signal points in the in-phase I-quadrature Q plane of thefirst transmission signal is 4, and the number of signal points in thein-phase I-quadrature Q plane of the second transmission signal is 16.

Transmission Method #8:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 16 and less than orequal to 256. However, when θ=0 radians in Equation (13) throughEquation (20), the number of signal points in the in-phase I-quadratureQ plane of the transmission signal is 16.

Transmission Method #9:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 64 and less than orequal to 4096. However, when θ=0 radians in Equation (13) throughEquation (20), the number of signal points in the in-phase I-quadratureQ plane of the transmission signal is 64.

As described above, the maximum number of signal points when thetransmission device illustrated in FIG. 1 transmits the single streammodulated signal is 64.

When the influence of phase noise in RF (radio frequency) unit includedin radio units 107_A, 107_B in the transmission device illustrated inFIG. 1 and the influence of non-linear distortion in the transmissionpower amplifier included in radio units 107_A, 107_B are taken intoconsideration, a modulation scheme in which the PAPR (peak-to-averagepower ratio) is low and a modulation scheme having a signal pointarrangement that yields little phase noise influence are preferablyused. Taking these into consideration, it is preferable that the numberof signal points in the in-phase I-quadrature Q plane of thetransmission signal (modulated signal) be reduced. As described above,when the transmission device can select from a plurality of transmissionmethods, since, by minimizing the number of signal points in thein-phase I-quadrature Q plane in the transmission method having thelargest number of signal points in the in-phase I-quadrature Q plane,influence of phase noise in the RF unit can be inhibited and influenceof non-linear distortion in the transmission power amplifier can beinhibited in the transmission device, in the reception device thatreceives the modulated signal transmitted by the transmission deviceillustrated in FIG. 1 , it is possible to achieve an advantageous effectthat the data reception quality is improved. Moreover, when thetransmission device illustrated in FIG. 1 transmits a modulated signalcharacterized by low phase noise influence in the RF unit and lownon-linear distortion in the transmission power amplifier, anadvantageous effect that the scale of the circuits for the RF unit andtransmission power amplifier in the transmission device can be reducedcan be achieved (when the PAPR greatly varies from modulation scheme tomodulation scheme, for example, an RF unit and transmission poweramplification unit need to be provided for each modulation scheme,thereby increasing the scale of circuitry).

As described above, the maximum number of signal points when thetransmission device illustrated in FIG. 1 transmits the single streammodulated signal is 64. Accordingly, if the maximum number of signalpoints when the transmission device illustrated in FIG. 1 transmits twostreams of modulated signals can be kept to 64, the above-describedadvantageous effects can be achieved.

On the other hand, when the transmission device illustrated in FIG. 1transmits two streams of modulated signals, and the s1(i) signal istransmitted from a plurality of antennas and the s2(i) signal istransmitted from a plurality of antennas, the advantageous effects oftransmit diversity are achieved, so the reception device that receivesthe modulated signal transmitted by the transmission device illustratedin FIG. 1 can achieve the advantageous effect that data receptionquality is improved. However, in order to achieve this advantageouseffect, it is important that the modulated signal transmitted by thetransmission device illustrated in FIG. 1 exhibit a small phase noiseinfluence in the RF unit and a small non-linear distortion influence inthe transmission power amplifier.

In view of this, consider a first or second selection method.

First Selection Method:

The transmission device illustrated in FIG. 1 switches the transmissionmethod of the modulated signal based on information on the transmissionmethod included in control signal 100. Here, the transmission deviceillustrated in FIG. 1 can select the following transmission methods.

Transmission Method #1-1:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #1-2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #1-3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or a modulation scheme inwhich 16 signal points are in the in-phase I-quadrature Q plane, such as16APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #1-4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or a modulation scheme inwhich 64 signal points are in the in-phase I-quadrature Q plane, such as64APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #1-5:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is BPSK (or π/2 shift BPSK), and themodulation scheme of s2(i) is BPSK (or π/2 shift BPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #1-6:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is QPSK (or π/2 shift QPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #1-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)) (when θ=π/4 radians (45degrees), the average transmission power of the modulated signalstransmitted from the antennas is equal).

Transmission Method #1-8:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ=0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #1-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ=0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Note that in the first selection method, the transmission method neednot correspond to all transmission methods from transmission method #1-1to transmission method #1-9. For example, in the first selection method,the transmission method may correspond to one or more transmissionmethod from among the following three transmission methods: transmissionmethod #1-5, transmission method #1-6, and transmission method #1-7. Inthe first transmission method, the transmission method may correspond toone or more transmission method from among the following twotransmission methods: transmission method #1-8 and transmission method#1-9.

In the first selection method, the transmission method need notcorrespond to transmission method #1-1 (in the first selection method,the transmission method need not include transmission method #1-1 in thetransmission method selection candidates in the transmission deviceillustrated in FIG. 1 ).

The first selection method may include a transmission method other thanthose from transmission method #1-1 to transmission method #1-9.

Here, the following is satisfied.

Transmission Method #1-1:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #1-2:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #1-3:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #1-4:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Transmission Method #1-5:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 2 and less than or equal to 4. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #1-6:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 16. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #1-7:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 64. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #1-8:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #1-9:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Since the above-described characteristics are achieved, by using thefirst selection method, in the transmission device illustrated in FIG. 1, influence of phase noise in RF unit and influence of non-lineardistortion in transmission power amplifier can be reduced, andadvantageous effect of transmit diversity is achievable in transmissionmethod #1-5 through transmission method #1-7. Accordingly, in thereception device that receives the modulated signal transmitted by thetransmission device illustrated in FIG. 1 , it is possible to achieve anadvantageous effect of improvement in data reception quality.

Second Selection Method:

Transmission Method #2-1:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #2-2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #2-3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or a modulation scheme inwhich 16 signal points are in the in-phase I-quadrature Q plane, such as16APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #2-4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or a modulation scheme inwhich 64 signal points are in the in-phase I-quadrature Q plane, such as64APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #2-5:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is BPSK (or π/2 shift BPSK), and themodulation scheme of s2(i) is BPSK (or π/2 shift BPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #2-6:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is QPSK (or π/2 shift QPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #2-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)) (when θ=π/4 radians (45degrees), the average transmission power of the modulated signalstransmitted from the antennas is equal).

Transmission Method #2-8:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ=0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #2-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ=0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Note that in the second selection method, the transmission method neednot correspond to all transmission methods from transmission method #2-1to transmission method #2-9. For example, in the second selectionmethod, the transmission method may correspond to one or moretransmission method from among the following three transmission methods:transmission method #2-5, transmission method #2-6, and transmissionmethod #2-7. In the second transmission method, the transmission methodmay correspond to one or more transmission method from among thefollowing two transmission methods: transmission method #2-8 andtransmission method #2-9.

In the second selection method, the transmission method need notcorrespond to transmission method #2-1 (in the second selection method,the transmission method need not include transmission method #2-1 in thetransmission method selection candidates in the transmission deviceillustrated in FIG. 1 ).

The second selection method may include a transmission method other thanthose from transmission method #2-1 to transmission method #2-9. Here,the following is satisfied.

Transmission Method #2-1:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #2-2:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #2-3:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #2-4:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Transmission Method #2-5:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 2 and less than or equalto 4. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #2-6:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 4 and less than or equalto 16. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #2-7:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 64. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #2-8:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #2-9:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Since the above-described characteristics are achieved, by using thesecond selection method, in the transmission device illustrated in FIG.1 , influence of phase noise in RF unit and influence of non-lineardistortion in transmission power amplifier can be reduced, and there arecases in which the advantageous effect of transmit diversity isachievable in transmission method #2-5 through transmission method #2-7.Accordingly, in the reception device that receives the modulated signaltransmitted by the transmission device illustrated in FIG. 1 , it ispossible to achieve an advantageous effect of improvement in datareception quality.

Moreover, a third selection method, which is a combination of the firstselection method and the second selection method, may be used.

Third Selection Method:

The transmission device illustrated in FIG. 1 switches the transmissionmethod of the modulated signal based on information on the transmissionmethod included in control signal 100. Here, the transmission methodillustrated in FIG. 1 can select the following transmission methods.

Transmission Method #3-1:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #3-2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #3-3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or a modulation scheme inwhich 16 signal points are in the in-phase I-quadrature Q plane, such as16APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #3-4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or a modulation scheme inwhich 64 signal points are in the in-phase I-quadrature Q plane, such as64APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #3-5:

Either one of transmission method #1-5 or transmission method #2-5.

Transmission Method #3-6:

Either one of transmission method #1-6 or transmission method #2-6.

Transmission Method #3-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #3-8:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ=0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #3-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ=0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Note that in the third selection method, the transmission method neednot correspond to all transmission methods from transmission method #3-1to transmission method #3-9. For example, in the third selection method,the transmission method may correspond to one or more transmissionmethod from among the following three transmission methods: transmissionmethod #3-5, transmission method #3-6, and transmission method #3-7. Inthe third transmission method, the transmission method may correspond toone or more transmission method from among the following twotransmission methods: transmission method #3-8 and transmission method#3-9.

In the third selection method, the transmission method need notcorrespond to transmission method #3-1 (in the third selection method,the transmission method need not include transmission method #3-1 in thetransmission method selection candidates in the transmission deviceillustrated in FIG. 1 ).

The third selection method may include a transmission method other thanthose from transmission method #3-1 to transmission method #3-9.

Since the above-described characteristics are achieved, by using thethird selection method, in the transmission device illustrated in FIG. 1, influence of phase noise in RF unit and influence of non-lineardistortion in transmission power amplifier can be reduced, and there arecases in which the advantageous effect of transmit diversity isachievable in transmission method #3-5 through transmission method #3-7.Accordingly, in the reception device that receives the modulated signaltransmitted by the transmission device illustrated in FIG. 1 , it ispossible to achieve an advantageous effect of improvement in datareception quality.

FIG. 5 illustrates one example of a configuration of radio units 107_Aand 107_B illustrated in FIG. 1 when the transmission device illustratedin FIG. 1 has an OFDM (orthogonal frequency division multiplexing)configuration. Serial-parallel converter 502 receives inputs of signal501 and control signal 500 (control signal 100 in FIG. 1 ), applies aserial-parallel conversion based on control signal 500, and outputsserial-parallel converted signal 503.

Inverse Fourier transform unit 504 receives inputs of serial-parallelconverted signal 503 and control signal 500, and based on control signal500, applies, as one example of an inverse Fourier transform, an IFFT(inverse fast Fourier transform), and outputs inverse Fouriertransformed signal 505.

Processor 506 receives inputs of inverse Fourier transformed signal 505and control signal 500, applies processing such as frequency conversionand amplification based on control signal 500, and outputs modulatedsignal 507.

(For example, when signal 501 is signal-processed signal 106_Aillustrated in FIG. 1 , modulated signal 507 corresponds to transmissionsignal 108_A in FIG. 1 . Moreover, when signal 501 is signal-processedsignal 106_B illustrated in FIG. 1 , modulated signal 507 corresponds totransmission signal 108_B in FIG. 1 .)

FIG. 6 illustrates a frame configuration of transmission signal 108_Aillustrated in FIG. 1 . In FIG. 6 , frequency (carriers) is (are)represented on the horizontal axis and time is represented on thevertical axis. Since a multi-carrier transmission method such as OFDM isused, symbols are present in the carrier direction. In FIG. 6 , symbolsfrom carriers 1 to 36 are shown. Moreover, in FIG. 6 , symbols for time$1 through time $11 are shown.

In FIG. 6, 601 is a pilot symbol (pilot signal 251A (pa(t) in FIG. 2 ,FIG. 3 )), 602 is a data symbol, and 603 is an other symbol. Here, apilot symbol is, for example, a PSK (phase shift keying) symbol, and isa symbol for the reception device that receives this frame to performchannel estimation (propagation path fluctuation estimation), frequencyoffset estimation, and phase fluctuation estimation. For example, thetransmission device illustrated in FIG. 1 and the reception device thatreceives the frame illustrated in FIG. 6 may share the transmissionmethod of the pilot symbol.

Note that mapped signal 201A (mapped signal 105_1 in FIG. 1 ) isreferred to as “stream #1” and mapped signal 201B (mapped signal 105_2in FIG. 1 ) is referred to as “stream #2”. Note that this also appliedto subsequent descriptions.

Data symbol 602 is a symbol that corresponds to a data symbol includedin baseband signal 208A generated in the signal processing illustratedin FIG. 2 , FIG. 3 . Accordingly, data symbol 602 satisfies “a symbolincluding both the symbol “stream #1” and the symbol “stream #2””, “thesymbol “stream #1””, or “the symbol “stream #2””, as determined by theconfiguration of the precoding matrix used by weighting synthesizer 203(in other words, data symbol 602 corresponds to weighting synthesizedsignal 204A (z1(i))).

Other symbols 603 are symbols corresponding to preamble signal 252 andcontrol information symbol signal 253 illustrated in FIG. 2 , FIG. 3(however, the other symbols may include symbols other than a preamble orcontrol information symbol). Here, a preamble may transmit data (controldata), and may be configured as, for example, a symbol for signaldetection, a signal for performing frequency and time synchronization,or a symbol for performing channel estimation (a symbol for performingpropagation path fluctuation estimation). The control information symbolis a symbol including control information for the reception device thatreceived the frame in FIG. 6 to demodulate and decode a data symbol.

For example, carriers $1 to 36 from time $1 to time $4 in FIG. 6 areother symbols 603. Then, at time $5, carrier 1 through carrier 11 aredata symbols 602. Thereafter, at time $5, carrier 12 is pilot symbol601, at time $5, carriers 13 to 23 are data symbols 602, at time $5,carrier 24 is pilot symbol 601 . . . at time $6, carriers 1 and 2 aredata symbols 602, at time $6, carrier 3 is pilot symbol 601 . . . attime $11, carrier 30 is pilot symbol 601, at time $11, carriers 31 to 36are data symbols 602.

FIG. 7 illustrates a frame configuration of transmission signal 108_Billustrated in FIG. 1 . In FIG. 7 , frequency (carriers) is (are)represented on the horizontal axis and time is represented on thevertical axis. Since a multi-carrier transmission method such as OFDM isused, symbols are present in the carrier direction. In FIG. 7 , symbolsfrom carriers 1 to 36 are shown. Moreover, in FIG. 7 , symbols for time$1 through time $11 are shown.

In FIG. 7, 701 is a pilot symbol (pilot signal 251B (pb(t) in FIG. 2 ,FIG. 3 )), 702 is a data symbol, and 703 is an other symbol. Here, apilot symbol is, for example, a PSK symbol, and is a symbol for thereception device that receives this frame to perform channel estimation(propagation path fluctuation estimation), frequency offset estimation,and phase fluctuation estimation. For example, the transmission deviceillustrated in FIG. 1 and the reception device that receives the frameillustrated in FIG. 7 may share the transmission method of the pilotsymbol.

Data symbol 702 is a symbol that corresponds to a data symbol includedin baseband signal 208B generated in the signal processing illustratedin FIG. 2 , FIG. 3 . Accordingly, data symbol 702 satisfies “a symbolincluding both the symbol “stream #1” and the symbol “stream #2””, “thesymbol “stream #1””, or “the symbol “stream #2””, as determined by theconfiguration of the precoding matrix used by weighting synthesizer 203(in other words, data symbol 702 corresponds to phase-changed signal206B (z2(i))).

Other symbols 703 are symbols corresponding to preamble signal 252 andcontrol information symbol signal 253 illustrated in FIG. 2 , FIG. 3(however, the other symbols may include symbols other than a preamble orcontrol information symbol). Here, a preamble may transmit data (controldata), and is configured as, for example, a symbol for signal detection,a signal for performing frequency and time synchronization, or a symbolfor performing channel estimation (a symbol for performing propagationpath fluctuation estimation). The control information symbol is a symbolincluding control information for the reception device that received theframe in FIG. 7 to demodulate and decode a data symbol.

For example, carriers 1 to 36 from time $1 to time $4 in FIG. 7 areother symbols 703. Then, at time $5, carrier 1 through carrier 11 aredata symbols 702. Thereafter, at time $5, carrier 12 is pilot symbol701, at time $5, carriers 13 to 23 are data symbols 702, at time $5,carrier 24 is pilot symbol 701 . . . at time $6, carriers 1 and 2 aredata symbols 702, at time $6, carrier 3 is pilot symbol 701 . . . attime $11, carrier 30 is pilot symbol 701, at time $11, carriers 31 to 36are data symbols 702.

When a symbol is present in carrier A at time $B in FIG. 6 and a symbolis present in carrier A at time $B in FIG. 7 , the symbol in carrier Aat time $B in FIG. 6 and the symbol in carrier A at time $B in FIG. 5are transmitted at the same time and same frequency. Note that the frameconfiguration is not limited to the configurations illustrated in FIG. 6and FIG. 7 ; FIG. 6 and FIG. 7 are mere examples of frameconfigurations.

The other symbols in FIG. 6 and FIG. 7 are symbols corresponding to“preamble signal 252 and control symbol 253 in FIG. 2 , FIG. 3 ”.Accordingly, when an other symbol 603 in FIG. 6 at the same time andsame frequency (same carrier) as an other symbol 703 in FIG. 7 transmitscontrol information, it transmits the same data (the same controlinformation).

Note that this is under the assumption that the frame of FIG. 6 and theframe of FIG. 7 are received at the same time by the reception device,but even when the frame of FIG. 6 or the frame of FIG. 7 has beenreceived, the reception device can obtain the data transmitted by thetransmission device.

FIG. 8 illustrates one example of components relating to controlinformation generation for generating control information symbol signal253 illustrated in FIG. 2 , FIG. 3 .

Control information mapper 802 receives inputs of data 801 related tocontrol information and control signal 800, maps data 801 related tocontrol information in using a modulation scheme based on control signal800, and outputs control information mapped signal 803. Note thatcontrol information mapped signal 803 corresponds to control informationsymbol signal 253 in FIG. 2 , FIG. 3 .

FIG. 9 illustrates one example of a configuration of antenna unit #A(109_A), antenna #B (109_B) illustrated in FIG. 1 (antenna unit #A(109_A) and antenna unit #B (109_B) are exemplified as including aplurality of antennas).

Splitter 902 receives an input of transmission signal 901, performssplitting, and outputs transmission signals 903_1, 903_2, 903_3, and903_4.

Multiplier 904_1 receives inputs of transmission signal 903_1 andcontrol signal 900, and based on the multiplication coefficient includedin control signal 900, multiplies a multiplication coefficient withtransmission signal 903_1, and outputs multiplied signal 905_1.Multiplied signal 905_1 is output from antenna 906_1 as radio waves.

When transmission signal 903_1 is expressed as Tx1(t) (t is time) andthe multiplication coefficient is expressed as W1 (W1 can be defined asa complex number and thus may be a real number), multiplied signal 905_1can be expressed as Tx1(t)×W1.

Multiplier 904_2 receives inputs of transmission signal 903_2 andcontrol signal 900, and based on the multiplication coefficient includedin control signal 900, multiplies a multiplication coefficient withtransmission signal 903_2, and outputs multiplied signal 905_2.Multiplied signal 905_2 is output from antenna 906_2 as radio waves.

When transmission signal 903_2 is expressed as Tx2(t) and themultiplication coefficient is expressed as W2 (W2 can be defined as acomplex number and thus may be a real number), multiplied signal 905_2can be expressed as Tx2(t)×W2.

Multiplier 904_3 receives inputs of transmission signal 903_3 andcontrol signal 900, and based on the multiplication coefficient includedin control signal 900, multiplies a multiplication coefficient withtransmission signal 903_3, and outputs multiplied signal 905_3.Multiplied signal 905_3 is output from antenna 906_3 as radio waves.

When transmission signal 903_3 is expressed as Tx3(t) and themultiplication coefficient is expressed as W3 (W3 can be defined as acomplex number and thus may be a real number), multiplied signal 905_3can be expressed as Tx3(t)×W3.

Multiplier 904_4 receives inputs of transmission signal 903_4 andcontrol signal 900, and based on the multiplication coefficient includedin control signal 900, multiplies a multiplication coefficient withtransmission signal 903_4, and outputs multiplied signal 905_4.Multiplied signal 905_4 is output from antenna 906_4 as radio waves.

When transmission signal 903_4 is expressed as Tx4(t) and themultiplication coefficient is expressed as W4 (W4 can be defined as acomplex number and thus may be a real number), multiplied signal 905_4can be expressed as Tx4(t)×W4.

Note that “the absolute value of W 1, the absolute value of W2, theabsolute value of W3, and the absolute value of W4 are equal” may betrue.

Here, this is the equivalent of having performed a phase change (it goeswithout saying that the absolute value of W1, the absolute value of W2,the absolute value of W3, and the absolute value of W4 may be unequal).

Moreover, in FIG. 9 , the antenna unit is exemplified as including fourantennas (and four multipliers), but the number of antennas is notlimited to four; the antenna unit may include two or more antennas.

When the configuration of antenna unit #A (109_A) in FIG. 1 is asillustrated in FIG. 9 , transmission signal 901 corresponds totransmission signal 108_A in FIG. 1 . When the configuration of antennaunit #B (109_B) in FIG. 1 is as illustrated in FIG. 9 , transmissionsignal 901 corresponds to transmission signal 108_B in FIG. 1 andtransmission signal 108_B in FIG. 1 . However, antenna unit #A (109_A)and antenna unit #B (109_B) need not have the configurations illustratedin FIG. 9 ; as previously described, the antenna units need not receivean input of control signal 100. For example, antenna unit #A (109_A),antenna unit #B (109_B) illustrated in FIG. 1 may include one antennaand, alternatively, may include a plurality of antennas.

FIG. 10 illustrates an example of a frame configuration of transmissionsignal 108_A illustrated in FIG. 1 . In FIG. 10 , time is represented onthe horizontal axis. The difference between FIG. 10 and FIG. 6 is thatthe frame configuration illustrated in FIG. 10 is an example of a frameconfiguration when a single-carrier scheme is used, and symbols arepresent along the time axis. In FIG. 10 , symbols from time t1 to t22are shown.

Preamble 1001 in FIG. 10 corresponds to preamble signal 252 in, forexample, FIG. 2 , FIG. 3 . Here, for example, the preamble may transmitdata (for control purposes), may be a symbol for signal detection, asymbol for frequency and time synchronization, or a symbol for channelestimation (a symbol for propagation path fluctuation estimation).

Control information symbol 1002 in FIG. 10 is a symbol that correspondsto control information symbol signal 253 in, for example, FIG. 2 , FIG.3 , and is a symbol including control information for realizingdemodulation and decoding of data symbols by the reception device thatreceived the frame illustrated in FIG. 10 .

Pilot symbol 1004 illustrated in FIG. 10 is a symbol corresponding topilot signal 251A (pa(t)) such as in FIG. 2 , FIG. 3 . Pilot symbol 1004is, for example, a PSK symbol, and is used by the reception device thatreceives the frame for, for example, channel estimation (propagationpath variation estimation), frequency offset estimation, and phasevariation estimation. For example, the transmission device illustratedin FIG. 1 and the reception device that receives the frame illustratedin FIG. 10 may share the pilot symbol transmission method.

1003 in FIG. 10 is a data symbol for transmitting data.

Note that mapped signal 201A (mapped signal 105_1 in FIG. 1 ) isreferred to as “stream #1” and mapped signal 201B (mapped signal 105_2in FIG. 1 ) is referred to as “stream #2”.

Data symbol 1003 is a symbol that corresponds to a data symbol includedin baseband signal 208A generated in the signal processing illustratedin FIG. 2 , FIG. 3 . Accordingly, data symbol 1003 satisfies “a symbolincluding both the symbol “stream #1” and the symbol “stream #2””, “thesymbol “stream #1””, or “the symbol “stream #2””, as determined by theconfiguration of the precoding matrix used by weighting synthesizer 203(in other words, data symbol 1003 corresponds to weighting synthesizedsignal 204A (z1(i))).

Note that, although not illustrated in FIG. 10 , the frame may includesymbols other than a preamble, control information symbol, data symbol,and pilot symbol.

For example, in FIG. 10 , the transmission device transmits preamble1001 at time t1, transmits control information symbol 1002 at time t2,transmits data symbols 1003 from time t3 to time t11, transmits pilotsymbol 1004 at time t12, transmits data symbols 1003 from time t13 totime t21, and transmits pilot symbol 1004 at time t22.

FIG. 11 illustrates an example of a frame configuration of transmissionsignal 108_B illustrated in FIG. 1 . In FIG. 11 , time is represented onthe horizontal axis. The difference between FIG. 11 and FIG. 7 is thatthe frame configuration illustrated in FIG. 11 is an example of a frameconfiguration when a single-carrier scheme is used, and symbols arepresent along the time axis. In FIG. 11 , symbols from time t1 to t22are shown.

Preamble 1101 in FIG. 11 corresponds to preamble signal 252 in, forexample, FIG. 2 , FIG. 3 . Here, a preamble may transmit data (forcontrol purposes), and may be configured as, for example, a symbol forsignal detection, a signal for performing frequency and timesynchronization, or a symbol for performing channel estimation (a symbolfor performing propagation path fluctuation estimation).

Control information symbol 1102 in FIG. 11 is a symbol that correspondsto control information symbol signal 253 in, for example, FIG. 2 , FIG.3 , and is a symbol including control information for realizingdemodulation and decoding of data symbols by the reception device thatreceived the frame illustrated in FIG. 11 .

Pilot symbol 1104 illustrated in FIG. 11 is a symbol corresponding topilot signal 251B (pb(t)) such as in FIG. 2 , FIG. 3 . Pilot symbol 1104is, for example, a PSK symbol, and is used by the reception device thatreceives the frame for, for example, channel estimation (propagationpath variation estimation), frequency offset estimation, and phasevariation estimation. For example, the transmission device illustratedin FIG. 1 and the reception device that receives the frame illustratedin FIG. 11 may share the pilot symbol transmission method.

1103 in FIG. 11 is a data symbol for transmitting data.

Note that mapped signal 201A (mapped signal 105_1 in FIG. 1 ) isreferred to as “stream #1” and mapped signal 201B (mapped signal 105_2in FIG. 1 ) is referred to as “stream #2”.

Data symbol 1103 is a symbol that corresponds to a data symbol includedin baseband signal 208B generated in the signal processing illustratedin FIG. 2 , FIG. 3 . Accordingly, data symbol 1103 satisfies “a symbolincluding both the symbol “stream #1” and the symbol “stream #2””, “thesymbol “stream #1””, or “the symbol “stream #2””, as determined by theconfiguration of the precoding matrix used by weighting synthesizer 203(in other words, data symbol 1103 corresponds to phase-changed signal206B (z2(i))).

Note that, although not illustrated in FIG. 11 , the frame may includesymbols other than a preamble, control information symbol, data symbol,and pilot symbol.

For example, in FIG. 11 , the transmission device transmits preamble1101 at time t1, transmits control information symbol 1102 at time t2,transmits data symbols 1103 from time t3 to time t11, transmits pilotsymbol 1104 at time t12, transmits data symbols 1103 from time t13 totime t21, and transmits pilot symbol 1104 at time t22.

When a symbol is present at time tp in FIG. 10 and a symbol is presentat time tp in FIG. 10 (where p is an integer that is greater than orequal to 1), the symbol at time tp in FIG. 10 and the symbol at time tpin FIG. 11 are transmitted at the same time and same frequency (forexample, the data symbol at time t3 in FIG. 10 and the data symbol attime t3 in FIG. 11 are transmitted at the same time and same frequency).Note that the frame configuration is not limited to the configurationsillustrated in FIG. 10 and FIG. 11 ; FIG. 10 and FIG. 11 are mereexamples of frame configurations.

Moreover, a method in which the preamble and control information symbolin FIG. 10 and FIG. 11 transmit the same data (same control information)may be used.

Note that this is under the assumption that the frame of FIG. 10 and theframe of FIG. 11 are received at the same time by the reception device,but even when the frame of FIG. 10 or the frame of FIG. 11 has beenreceived, the reception device can obtain the data transmitted by thetransmission device.

FIG. 12 illustrates an example of a method of arranging symbols on thetime axis for weighting synthesized signal 204A (z1(i)) andphase-changed signal 206B (z2(i)).

In FIG. 12 , for example, zp(0) is shown. Here, q is 1 or 2.Accordingly, zp(0) in FIG. 12 indicates “in z1(i) and z2(i), z1(0) andz2(0) when symbol number i=0”. Similarly, zp(1) indicates “in z1(i) andz2(i), z1(1) and z2(1) when symbol number i=1” (in other words, zp(X)indicates “in z1(i) and z2(i), z1(X) and z2(X) when symbol number i=X”).Note that this also applies to FIG. 13 , FIG. 14 , and FIG. 15 .

As illustrated in FIG. 12 , symbol zp(0) whose symbol number i=0 isarranged at time 0, symbol zp(1) whose symbol number i=1 is arranged attime 1, symbol zp(2) whose symbol number i=2 is arranged at time 2,symbol zp(3) whose symbol number i=3 is arranged at time 3, and othersymbols are arranged in a similar fashion. With this, symbols arearranged on the time axis for weighting synthesized signal 204A (z1(i))and phase-changed signal 206B (z2(i)). However, FIG. 12 merelyillustrates one example; the relationship between time and symbol numberis not limited to this example.

FIG. 13 illustrates an example of a method of arranging symbols on thefrequency axis for weighting synthesized signal 204A (z1(i)) andphase-changed signal 206B (z2(i)).

As illustrated in FIG. 13 , symbol zp(0) whose symbol number i=0 isarranged at carrier 0, symbol zp(1) whose symbol number i=1 is arrangedat carrier 1, symbol zp(2) whose symbol number i=2 is arranged atcarrier 2, symbol zp(3) whose symbol number i=3 is arranged at carrier3, and other symbols are arranged in a similar fashion. With this,symbols are arranged on the frequency axis for weighting synthesizedsignal 204A (z1(i)) and phase-changed signal 206B (z2(i)). However, FIG.13 merely illustrates one example; the relationship between frequencyand symbol number is not limited to this example.

FIG. 14 illustrates an example of an arrangement of symbols on the timeand frequency axes for weighting synthesized signal 204A (z1(i)) andphase-changed signal 206B (z2(i)).

As illustrated in FIG. 14 , symbol zp(0) whose symbol number i=0 isarranged at time 0 and carrier 0, symbol zp(1) whose symbol number i=1is arranged at time 0 and carrier 1, symbol zp(2) whose symbol numberi=2 is arranged at time 1 and carrier 0, symbol zp(3) whose symbolnumber i=3 is arranged at time 1 and carrier 1, and other symbols arearranged in a similar fashion. With this, symbols are arranged on thetime and frequency axes for weighting synthesized signal 204A (z1(i))and phase-changed signal 206B (z2(i)). However, FIG. 14 merelyillustrates one example; the relationship between time and frequency andsymbol number is not limited to this example.

FIG. 15 illustrates an example of an arrangement of symbols relative totime for weighting synthesized signal 204A (z1(i)) and phase-changedsignal 206B (z2(i)). Note FIG. 15 illustrates an example of anarrangement of symbols when an interleaver (component for rearrangingsymbols) is included in radio units 107_A, 107_B illustrated in FIG. 1(note that the configuration of radio units 107_A, 107B illustrated inFIG. 1 when including an interleaver (component for rearranging symbols)will be described later with reference to FIG. 18 ).

As illustrated in FIG. 15 , symbol zp(0) whose symbol number i=0 isarranged at time 0, symbol zp(1) whose symbol number i=1 is arranged attime 16, symbol zp(2) whose symbol number i=2 is arranged at time 12,symbol zp(3) whose symbol number i=3 is arranged at time 5, and othersymbols are arranged in a similar fashion. With this, symbols arearranged on the time axis for weighting synthesized signal 204A (z1(i))and phase-changed signal 206B (z2(i)). However, FIG. 15 merelyillustrates one example; the relationship between time and symbol numberis not limited to this example.

FIG. 16 illustrates an example of an arrangement of symbols relative totime for weighting synthesized signal 204A (z1(i)) and phase-changedsignal 206B (z2(i)). Note FIG. 16 illustrates an example of anarrangement of symbols when an interleaver (component for rearrangingsymbols) is included in radio units 107_A, 107_B illustrated in FIG. 1(note that the configuration of radio units 107_A, 107_B illustrated inFIG. 1 when including an interleaver (component for rearranging symbols)will be described later with reference to FIG. 18 ).

As illustrated in FIG. 16 , symbol zp(0) whose symbol number i=0 isarranged at carrier 0, symbol zp(1) whose symbol number i=1 is arrangedat carrier 16, symbol zp(2) whose symbol number i=2 is arranged atcarrier 12, symbol zp(3) whose symbol number i=3 is arranged at carrier5, and other symbols are arranged in a similar fashion. With this,symbols are arranged on the time axis for weighting synthesized signal204A (z1(i)) and phase-changed signal 206B (z2(i)). However, FIG. 16merely illustrates one example; the relationship between frequency andsymbol number is not limited to this example.

FIG. 17 illustrates an example of an arrangement of symbols relative totime for weighting synthesized signal 204A (z1(i)) and phase-changedsignal 206B (z2(i)). Note FIG. 17 illustrates an example of anarrangement of symbols when an interleaver (component for rearrangingsymbols) is included in radio units 107_A, 107_B illustrated in FIG. 1(note that the configuration of radio units 107_A, 107_B illustrated inFIG. 1 when including an interleaver (component for rearranging symbols)will be described later with reference to FIG. 18 ).

As illustrated in FIG. 17 , symbol zp(0) whose symbol number i=0 isarranged at time 1 and carrier 1, symbol zp(1) whose symbol number i=1is arranged at time 3 and carrier 3, symbol zp(2) whose symbol numberi=2 is arranged at time 1 and carrier 0, symbol zp(3) whose symbolnumber i=3 is arranged at time 1 and carrier 3, and other symbols arearranged in a similar fashion. With this, symbols are arranged on thetime and frequency axes for weighting synthesized signal 204A (z1(i))and phase-changed signal 206B (z2(i)). However, FIG. 17 merelyillustrates one example; the relationship between time and frequency andsymbol number is not limited to this example.

FIG. 18 illustrates an example of arrangement of symbols when radiounits 107_A, 107_B illustrated in FIG. 1 include an interleaver(component for rearranging symbols).

Interleaver (rearranger) 1802 receives inputs of signal-processed signal1801 (corresponding to 105_1, 105_2 in FIG. 1 ) and control signal 1800(corresponding to 100 in FIG. 1 ), and, for example, in accordance withcontrol signal 1800, rearrange the symbols, and output rearranged signal1803. Note that an example of the rearrangement of symbols is asdescribed with reference to FIG. 14 through FIG. 17 .

Signal processor 1804 receives inputs of rearranged signal 1803 andcontrol signal 1800, and in accordance with control signal 1800,performs signal processing, and outputs signal-processed signal 1805.For example, when the transmission device illustrated in FIG. 1 supportsboth a single-carrier scheme and an OFDM scheme, based on control signal1800, signal processor 1804 either performs signal processing inaccordance with the single-carrier scheme or performs signal processingin accordance with the OFDM scheme.

RF unit 1806 receives inputs of signal-processed signal 1805 and controlsignal 1800, and based on control signal 1800, performs processing suchas frequency conversion, and outputs modulated signal 1807.

Transmission power amplifier 1808 receives an input of modulated signal1807, performs signal amplification, and outputs modulated signal 1809.

FIG. 19 illustrates one example of a configuration of a reception devicethat receives a modulated signal upon the transmission deviceillustrated in FIG. 1 transmitting, for example, the frame configurationillustrated in FIG. 6 or FIG. 7 , or a transmission signal illustratedin FIG. 10 or FIG. 11 .

Radio unit 1903X receives an input of reception signal 1902X received byantenna unit #X (1901X), applies processing such as frequency conversionand a Fourier transform, and outputs baseband signal 1904X.

Similarly, radio unit 1903Y receives an input of reception signal 1902Yreceived by antenna unit #Y (1901Y), applies processing such asfrequency conversion and a Fourier transform, and outputs basebandsignal 1904Y.

Note FIG. 19 illustrates a configuration in which antenna unit #X(1901X) and antenna unit #Y (1901Y) receive control signal 1910 as aninput, but antenna unit #X (1901X) and antenna unit #Y (1901Y) may beconfigured to not receive an input of control signal 1910. Operationsperformed when control signal 1910 is present as an input will bedescribed in detail later.

FIG. 20 illustrates the relationship between the transmission device andthe reception device. Antennas 2001_1 and 2001_2 in FIG. 20 aretransmitting antennas, and antenna 2001_1 in FIG. 20 corresponds toantenna unit #A (109_A) in FIG. 1 . Antenna 2001_2 in FIG. 20corresponds to antenna unit #B (109_B) in FIG. 1 .

Antennas 2002_1 and 2002_2 in FIG. 20 are receiving antennas, andantenna 2002_1 in FIG. 20 corresponds to antenna unit #X (1901X) in FIG.19 . Antenna 2002_2 in FIG. 20 corresponds to antenna unit #Y (1901Y) inFIG. 19 .

As illustrated in FIG. 20 , the signal transmitted from transmittingantenna 2001_1 is u1(i), the signal transmitted from transmittingantenna 2001_2 is u2(i), the signal received by receiving antenna 2002_1is r1(i), and the signal received by receiving antenna 2002_2 is r2(i)Note that i is a symbol number, and, for example, is an integer that isgreater than or equal to 0.

The propagation coefficient from transmitting antenna 2001_1 toreceiving antenna 2002_1 is h11(i), the propagation coefficient fromtransmitting antenna 2001_1 to receiving antenna 2002_2 is h21(i), thepropagation coefficient from transmitting antenna 2001_2 to receivingantenna 2002_1 is h12(i), and the propagation coefficient fromtransmitting antenna 2001_2 to receiving antenna 2002_2 is h22(i). Inthis case, the following relation equation holds true.

$\begin{matrix}\lbrack {{MATH}.46} \rbrack & \end{matrix}$ $\begin{matrix}{\begin{pmatrix}{r1(i)} \\{r2(i)}\end{pmatrix} = {{\begin{pmatrix}{h11(i)} & {h12(i)} \\{h21(i)} & {h22(i)}\end{pmatrix}\begin{pmatrix}{u1(i)} \\{u2(i)}\end{pmatrix}} + \begin{pmatrix}{n1(i)} \\{n2(i)}\end{pmatrix}}} & {{Equation}(46)}\end{matrix}$

Note that n1(i) and n2(i) are noise.

Channel estimation unit 1905_1 of modulated signal u1 in FIG. 19receives an input of baseband signal 1904X, and using the preambleand/or pilot symbol illustrated in FIG. 6 or FIG. 7 (or FIG. 10 or FIG.11 ), performs channel estimation on modulated signal u1, that is tosay, estimates h11(i) in Equation (46), and outputs channel estimatedsignal 1906_1.

Channel estimation unit 1905_2 of modulated signal u2 receives an inputof baseband signal 1904X, and using the preamble and/or pilot symbolillustrated in FIG. 6 or FIG. 7 (or FIG. 10 or FIG. 11 ), performschannel estimation on modulated signal u2, that is to say, estimatesh12(i) in Equation (46), and outputs channel estimated signal 1906_2.

Channel estimation unit 1907_1 of modulated signal u1 receives an inputof baseband signal 1904Y, and using the preamble and/or pilot symbolillustrated in FIG. 6 or FIG. 7 (or FIG. 10 or FIG. 11 ), performschannel estimation on modulated signal u1, that is to say, estimatesh21(i) in Equation (46), and outputs channel estimated signal 1908_1.

Channel estimation unit 1907_2 of modulated signal u2 receives an inputof baseband signal 1904Y, and using the preamble and/or pilot symbolillustrated in FIG. 6 or FIG. 7 (or FIG. 10 or FIG. 11 ), performschannel estimation on modulated signal u2, that is to say, estimatesh22(i) in Equation (46), and outputs channel estimated signal 1908_2.

Control information decoder 1909 receives inputs of baseband signals1904X and 1904Y, demodulates and decodes control information including“other symbols” in FIG. 6 and FIG. 7 (or FIG. 10 and FIG. 11 ), andoutputs control signal 1910 including control information.

Signal processor 1911 receives inputs of channel estimated signals1906_1, 1906_2, 1908_1, 1908_2, baseband signals 1904X, 1904Y, andcontrol signal 1910, and performs demodulation and decoding using therelationship in Equation (46) or based on control information in controlsignal 1910 (for example, information on a modulation scheme or a schemerelating to the error correction code), and outputs reception data 1912.

Note that control signal 1910 need not be generated via the methodillustrated in FIG. 19 . For example, control signal 1910 in FIG. 19 maybe generated based on information transmitted by a device that is thecommunication partner (FIG. 1 ) in FIG. 8 , and, alternatively, thedevice in FIG. 19 may include an input unit, and control signal 1910 maybe generated based on information input from the input unit.

FIG. 21 illustrates one example of a configuration of antenna unit #X(1901X) and antenna unit #Y (1901Y) illustrated in FIG. 19 (antenna unit#X (1901X) and antenna unit #Y (1901Y) are exemplified as including aplurality of antennas).

Multiplier 2103_1 receives inputs of reception signal 2102_1 received byantenna 2101_1 and control signal 2100, and based on information on amultiplication coefficient included in control signal 2100, multipliesreception signal 2102_1 with the multiplication coefficient, and outputsmultiplied signal 2104_1.

When reception signal 2102_1 is expressed as Rx1(t) (t is time) and themultiplication coefficient is expressed as D1 (D1 can be defined as acomplex number and thus may be a real number), multiplied signal 2104_1can be expressed as Rx1(t)×D1.

Multiplier 2103_2 receives inputs of reception signal 2102_2 received byantenna 2101_2 and control signal 2100, and based on information on amultiplication coefficient included in control signal 2100, multipliesreception signal 2102_2 with the multiplication coefficient, and outputsmultiplied signal 2104_2.

When reception signal 2102_2 is expressed as Rx2(t) and themultiplication coefficient is expressed as D2 (D2 can be defined as acomplex number and thus may be a real number), multiplied signal 2104_2can be expressed as Rx2(t)×D2.

Multiplier 2103_3 receives inputs of reception signal 2103_3 received byantenna 2101_3 and control signal 2100, and based on information on amultiplication coefficient included in control signal 2100, multipliesreception signal 2102_3 with the multiplication coefficient, and outputsmultiplied signal 2104_3.

When reception signal 2102_3 is expressed as Rx3(t) and themultiplication coefficient is expressed as D3 (D3 can be defined as acomplex number and thus may be a real number), multiplied signal 2104_3can be expressed as Rx3(t)×D3.

Multiplier 2103_4 receives inputs of reception signal 2102_4 received byantenna 2101_4 and control signal 2100, and based on information on amultiplication coefficient included in control signal 2100, multipliesreception signal 2102_4 with the multiplication coefficient, and outputsmultiplied signal 2104_4.

When reception signal 2102_4 is expressed as Rx4(t) and themultiplication coefficient is expressed as D4 (D4 can be defined as acomplex number and thus may be a real number), multiplied signal 2104_4can be expressed as Rx4(t)×D4.

Synthesizer 2105 receives inputs of multiplied signals 2104_1, 2104_2,2104_3, and 1004_4, synthesizes multiplied signals 2104_1, 2104_2,2104_3, and 2104_4, and outputs synthesized signal 2106. Note thatsynthesized signal 2106 is expressed asRx1(t)×D1+Rx2(t)×D2+Rx3(t)×D3+Rx4(t)×D4.

In FIG. 21 , the antenna unit is exemplified as including four antennas(and four multipliers), but the number of antennas is not limited tofour; the antenna unit may include two or more antennas.

When antenna unit #X (1901X) illustrated in FIG. 19 has theconfiguration illustrated in FIG. 21 , reception signal 1902Xcorresponds to synthesized signal 2106 in FIG. 21 , and control signal1910 corresponds to control signal 2100 in FIG. 10 . When antenna unit#Y (1901Y) illustrated in FIG. 19 has the configuration illustrated inFIG. 21 , reception signal 1902Y corresponds to synthesized signal 2106in FIG. 21 , and control signal 1910 corresponds to control signal 2100in FIG. 21 .

However, antenna unit #X (1901X) and antenna unit #Y (1901Y) need nothave the configurations illustrated in FIG. 21 ; as previouslydescribed, the antenna units need not receive an input of control signal1910. antenna unit #X (1901X) and antenna unit #Y (1901Y) may each becomprised on a single antenna.

Note that control signal 1900 may be generated based on informationtransmitted by a device that is the communication partner, and,alternatively, the device may include an input unit, and control signal1900 may be generated based on information input from the input unit.

With the transmission method described in this embodiment, by thetransmission device illustrated in FIG. 1 transmitting the modulatedsignal, the reception device in FIG. 19 that receives the modulatedsignal transmitted by the transmission device in FIG. 1 can reduce theinfluence of phase noise and the influence of non-linear distortion, andthus can achieve an advantageous effect that the data reception qualityis improved.

Note that the modulated signal transmitted by the transmission deviceillustrated in FIG. 1 may be a single-carrier scheme modulated signaland, alternatively, may be a multi-carrier scheme modulated signal suchas an OFDM modulated signal. Moreover, the modulated signal may beapplied with a spread spectrum communication method.

Control signal 100 in the transmission device illustrated in FIG. 1 mayinclude control information for specifying transmission using asingle-carrier scheme or transmission using a multi-carrier scheme suchas OFDM. When control signal 100 indicates transmission using asingle-carrier scheme, the transmission device illustrated in FIG. 1transmits a single-carrier scheme modulated signal, and when controlsignal 100 indicates transmission using a multi-carrier scheme such asOFDM, the transmission device illustrated in FIG. 1 transmits amulti-carrier scheme modulated signal such as an OFDM modulated signal.Note that as a result of the transmission signal illustrated in FIG. 1transmitting, to the reception device illustrated in FIG. 19 , controlinformation for specifying transmission using a single-carrier scheme ortransmission using a multi-carrier scheme such as OFDM, the receptiondevice illustrated in FIG. 19 can receive, demodulate, and decode themodulated signal transmitted in FIG. 1 .

Embodiment 2

In this embodiment, differences from Embodiment 1 will be described whenthe transmission device illustrated in FIG. 1 can transmit both asingle-carrier scheme modulated signal and a multi-carrier schememodulated signal such as an OFDM modulated signal, or one or the other.

In this embodiment, the following three types of transmission deviceswill be considered.

First Transmission Device:

The first transmission device is a transmission device capable ofselectively transmitting both a single-carrier scheme modulated signaland a multi-carrier scheme modulated signal such as an OFDM modulatedsignal. Control signal 100 in the transmission device illustrated inFIG. 1 includes control information for specifying transmission using asingle-carrier scheme or transmission using a multi-carrier scheme suchas OFDM, and when control signal 100 indicates transmission using asingle-carrier scheme, the transmission device illustrated in FIG. 1transmits a single-carrier scheme modulated signal, and when controlsignal 100 indicates transmission using a multi-carrier scheme such asOFDM, the transmission device illustrated in FIG. 1 transmits amulti-carrier scheme modulated signal such as an OFDM modulated signal.Note that as a result of the transmission device illustrated in FIG. 1transmitting, to the reception device illustrated in FIG. 19 , controlinformation for specifying transmission using a single-carrier scheme ortransmission using a multi-carrier scheme such as OFDM, the receptiondevice illustrated in FIG. 19 can receive, demodulate, and decode themodulated signal transmitted by the transmission device illustrated inFIG. 1 .

Second Transmission Device:

The second transmission device is a transmission device capable oftransmitting a single-carrier scheme modulated signal. When controlsignal 100 in the transmission device illustrated in FIG. 1 includescontrol information for specifying transmission using a single-carrierscheme or transmission using a multi-carrier scheme such as OFDM, thesecond transmission device can only select transmission using asingle-carrier scheme as this control information. Accordingly, thetransmission device illustrated in FIG. 1 transmits a single-carrierscheme modulated signal. Note that as a result of the transmissiondevice illustrated in FIG. 1 transmitting, to the reception deviceillustrated in FIG. 19 , control information for specifying transmissionusing a single-carrier scheme or transmission using a multi-carrierscheme such as OFDM, the reception device illustrated in FIG. 19 canreceive, demodulate, and decode the modulated signal transmitted by thetransmission device illustrated in FIG. 1 .

Third Transmission Device:

The third transmission device is a transmission device capable oftransmitting a multi-carrier scheme modulated signal such as an OFDMmodulated signal. When control signal 100 in the transmission deviceillustrated in FIG. 1 includes control information for specifyingtransmission using a single-carrier scheme or transmission using amulti-carrier scheme such as OFDM, the second transmission device canonly select transmission using a multi-carrier scheme such as OFMD asthis control information. Accordingly, the transmission deviceillustrated in FIG. 1 transmits a multi-carrier scheme modulated signalsuch as a OFDM modulated signal. Note that as a result of thetransmission device illustrated in FIG. 1 transmitting, to the receptiondevice illustrated in FIG. 19 , control information for specifyingtransmission using a single-carrier scheme or transmission using amulti-carrier scheme such as OFDM, the reception device illustrated inFIG. 19 can receive, demodulate, and decode the modulated signaltransmitted by the transmission device illustrated in FIG. 1 .

In Embodiment 1, the configuration of the transmission device, theconfiguration of the reception device that receives the modulated signaltransmitted by the transmission device, the frame configuration examplein the case of single-carrier scheme, and the frame configurationexample in the case of multi-carrier scheme such as OFDM have alreadybeen described, so repeated description will be omitted.

In this embodiment, as a transmission signal method for a modulatedsignal when a single-carrier scheme is used, any one of the firstselection method, second selection method, or third selection methoddescribed in Embodiment 1 is applied, and the transmission deviceillustrated in FIG. 1 transmits the modulated signal. Here, in thesecond transmission device, influence of phase noise in the RF unit andinfluence of non-linear distortion in the transmission power amplifiercan be reduced, and depending on the transmission method, it is possibleto achieve an advantageous effect of transmit diversity. Accordingly, inthe reception device that receives the modulated signal transmitted bythe second transmission device, it is possible to achieve anadvantageous effect of improvement in data reception quality.

In this embodiment, the following methods for transmitting amulti-carrier scheme modulated signal such as an OFDM modulated signalwill be considered.

Fourth Selection Method:

The transmission device illustrated in FIG. 1 switches the transmissionmethod of the modulated signal based on information on the transmissionmethod included in control signal 100. Here, the transmission deviceillustrated in FIG. 1 can select the following transmission methods.

Transmission Method #4-1:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #4-2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #4-3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or a modulation scheme inwhich 16 signal points are in the in-phase I-quadrature Q plane, such as16APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #4-4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or a modulation scheme inwhich 64 signal points are in the in-phase I-quadrature Q plane, such as64APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #4-5:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is BPSK (or π/2 shift BPSK), and themodulation scheme of s2(i) is BPSK (or π/2 shift BPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #4-6:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is QPSK (or π/2 shift QPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #4-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)) (when θ=π/4 radians (45degrees), the average transmission power of the modulated signalstransmitted from the antennas is equal).

Transmission Method #4-8:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #4-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 16APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)). Here, θ=0 radians inEquation (13) through Equation (20) (note that θ is greater than orequal to 0 radians and less than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Note that in the fourth selection method, the transmission method neednot correspond to all transmission methods from transmission method #4-1through transmission method #4-9. For example, in the fourth selectionmethod, the transmission method may correspond to one or moretransmission method from among the following three transmission methods:transmission method #4-5, transmission method #4-6, and transmissionmethod #4-7. In the fourth transmission method, the transmission methodmay correspond to one or more transmission method from among thefollowing two transmission methods: transmission method #4-8 andtransmission method #4-9.

In the fourth selection method, the transmission method need notcorrespond to transmission method #4-1 (in the fourth selection method,the transmission method need not include transmission method #4-1 in thetransmission method selection candidates in the transmission deviceillustrated in FIG. 1 ).

The fourth selection method may include a transmission method other thanthose from transmission method #4-1 to transmission method #4-9.

Here, the following is satisfied.

Transmission Method #4-1:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #4-2:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #4-3 The number of signal points in the in-phaseI-quadrature Q plane of the transmission signal is 16.

Transmission Method #4-4:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Transmission Method #4-5:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 2 and less than or equal to 4. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #4-6:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 16. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #4-7:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 64. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #4-8:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 16 and less than or equal to 256.The advantageous effect of transmit diversity is achievable.

Transmission Method #4-9:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 64 and less than orequal to 4096. The advantageous effect of transmit diversity may beachievable.

As described above, the selection method for the transmission methodwhen a single-carrier scheme modulated signal is transmitted and theselection method for the transmission method when a multi-carrier schememodulated signal such as an OFDM modulated signal is transmitted aredifferent.

The reason for why the fourth selection method is used as the selectionmethod for the transmission method when a multi-carrier scheme modulatedsignal such as an OFDM modulated signal is transmitted will bedescribed.

As a transmission device that transmits a multi-carrier scheme modulatedsignal such as an OFDM modulated signal, regardless of the modulationscheme used, it is necessary to satisfy the conditions that theinfluence of phase noise in the RF unit is small and the influence ofnon-linear distortion in the transmission power amplifier is small (whenthese conditions are not satisfied, in the reception device thatreceives the modulated signal transmitted by the transmission device, itis difficult to achieve high data reception quality (since thetransmission device transmits modulated signals for a plurality ofcarriers at the same time, regardless of the modulation scheme used, thePAPR is large, so the above-described conditions are important)).

Accordingly, when the transmission device illustrated in FIG. 1 is thethird transmission device (or the first transmission device), by usingthe fourth selection method, when a plurality of modulated signals aretransmitted, it is possible to increase the probability that high datareception quality can be achieved by the reception device, so performingprecoding is given as much priority as possible.

As described above, regardless of whether the transmission devicetransmits a single-carrier scheme modulated signal or a multi-carrierscheme modulated signal such as an OFDM modulated signal, the receptiondevice that receives the modulated signal transmitted by thetransmission device can achieve an advantageous effect that it ispossible to achieve an even higher data reception quality.

Next, a fifth selection method different than the fourth selectionmethod that is used when transmitting a multi-carrier scheme modulatedsignal such as an OFDM modulated signal will be described.

Fifth Selection Method:

Transmission Method #5-1:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #5-2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #5-3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or a modulation scheme inwhich 16 signal points are in the in-phase I-quadrature Q plane, such as16APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #5-4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or a modulation scheme inwhich 64 signal points are in the in-phase I-quadrature Q plane, such as64APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #5-5:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is BPSK (or π/2 shift BPSK), and themodulation scheme of s2(i) is BPSK (or π/2 shift BPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #5-6:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is QPSK (or π/2 shift QPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #5-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)) (when θ=π/4 radians (45degrees), the average transmission power of the modulated signalstransmitted from the antennas is equal).

Transmission Method #5-8:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #5-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 16APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)). Here, θ=0 radians inEquation (13) through Equation (20) (note that θ is greater than orequal to 0 radians and less than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Note that in the fifth selection method, the transmission method neednot correspond to all transmission methods from transmission method #5-1through transmission method #5-9. For example, in the fifth selectionmethod, the transmission method may correspond to one or moretransmission method from among the following three transmission methods:transmission method #5-5, transmission method #5-6, and transmissionmethod #5-7. In the fifth transmission method, the transmission methodmay correspond to one or more transmission method from among thefollowing two transmission methods: transmission method #5-8 andtransmission method #5-9.

In the fifth selection method, the transmission method need notcorrespond to transmission method #4-1 (in the fifth selection method,the transmission method need not include transmission method #5-1 in thetransmission method selection candidates in the transmission deviceillustrated in FIG. 1 ).

The fifth selection method may include a transmission method other thanthose from transmission method #5-1 to transmission method #5-9.

Here, the following is satisfied.

Transmission Method #5-1:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #5-2:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #5-3:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #5-4:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Transmission Method #5-5:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 2 and less than or equal to 4. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #5-6:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 16. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #5-7:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 64. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #5-8:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 16 and less than orequal to 256. The advantageous effect of transmit diversity may beachievable.

Transmission Method #5-9:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 64 and less than orequal to 4096. The advantageous effect of transmit diversity may beachievable.

As described above, the selection method for the transmission methodwhen a single-carrier scheme modulated signal is transmitted and theselection method for the transmission method when a multi-carrier schememodulated signal such as an OFDM modulated signal is transmitted aredifferent.

The reason for why the fifth selection method is used as the selectionmethod for the transmission method when a multi-carrier scheme modulatedsignal such as an OFDM modulated signal is transmitted will bedescribed.

As a transmission device that transmits a multi-carrier scheme modulatedsignal such as an OFDM modulated signal, regardless of the modulationscheme used, it is necessary to satisfy the conditions that theinfluence of phase noise in the RF unit is small and the influence ofnon-linear distortion in the transmission power amplifier is small (whenthese conditions are not satisfied, in the reception device thatreceives the modulated signal transmitted by the transmission device, itis difficult to achieve high data reception quality (since thetransmission device transmits modulated signals for a plurality ofcarriers at the same time, regardless of the modulation scheme used, thePAPR is large, so the above-described conditions are important)).

Accordingly, when the transmission device illustrated in FIG. 1 is thethird transmission device (or the first transmission device), by usingthe fifth selection method, when a plurality of modulated signals aretransmitted, it is possible to increase the probability that high datareception quality can be achieved by the reception device, so performingprecoding is given as much priority as possible.

As described above, regardless of whether the transmission devicetransmits a single-carrier scheme modulated signal or a multi-carrierscheme modulated signal such as an OFDM modulated signal, the receptiondevice that receives the modulated signal transmitted by thetransmission device can achieve an advantageous effect that it ispossible to achieve an even higher data reception quality.

Next, a sixth selection method different than the fourth selectionmethod and the fifth selection method that is used when transmitting amulti-carrier scheme modulated signal such as an OFDM modulated signalwill be described.

Sixth Selection Method:

Transmission Method #6-1:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #6-2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #6-3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or a modulation scheme inwhich 16 signal points are in the in-phase I-quadrature Q plane, such as16APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #6-4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or a modulation scheme inwhich 64 signal points are in the in-phase I-quadrature Q plane, such as64APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #6-5:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is BPSK (or π/2 shift BPSK), and themodulation scheme of s2(i) is BPSK (or π/2 shift BPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #6-6:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is QPSK (or π/2 shift QPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #6-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)) (when θ=π/4 radians (45degrees), the average transmission power of the modulated signalstransmitted from the antennas is equal).

Transmission Method #6-8:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #6-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 16APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)). Here, θ=0 radians inEquation (13) through Equation (20) (note that θ is greater than orequal to 0 radians and less than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Note that in the sixth selection method, the transmission method neednot correspond to all transmission methods from transmission method #6-1through transmission method #6-9. For example, in the sixth selectionmethod, the transmission method may correspond to one or moretransmission method from among the following three transmission methods:transmission method #6-5, transmission method #6-6, and transmissionmethod #6-7. In the sixth transmission method, the transmission methodmay correspond to one or more transmission method from among thefollowing two transmission methods: transmission method #6-8 andtransmission method #6-9.

In the sixth selection method, the transmission method need notcorrespond to transmission method #6-1 (in the sixth selection method,the transmission method need not include transmission method #6-1 in thetransmission method selection candidates in the transmission deviceillustrated in FIG. 1 ).

The sixth selection method may include a transmission method other thanthose from transmission method #6-1 to transmission method #6-9.

Here, the following is satisfied.

Transmission Method #6-1:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #6-2:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #6-3:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #6-4:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Transmission Method #6-5:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 2 and less than or equalto 4. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #6-6:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 4 and less than or equalto 16. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #6-7:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 64. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #6-8:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 16 and less than or equal to 256.The advantageous effect of transmit diversity is achievable.

Transmission Method #6-9:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 64 and less than orequal to 4096. The advantageous effect of transmit diversity may beachievable.

As described above, the selection method for the transmission methodwhen a single-carrier scheme modulated signal is transmitted and theselection method for the transmission method when a multi-carrier schememodulated signal such as an OFDM modulated signal is transmitted aredifferent.

The reason for why the sixth selection method is used as the selectionmethod for the transmission method when a multi-carrier scheme modulatedsignal such as an OFDM modulated signal is transmitted will bedescribed.

As a transmission device that transmits a multi-carrier scheme modulatedsignal such as an OFDM modulated signal, regardless of the modulationscheme used, it is necessary to satisfy the conditions that theinfluence of phase noise in the RF unit is small and the influence ofnon-linear distortion in the transmission power amplifier is small (whenthese conditions are not satisfied, in the reception device thatreceives the modulated signal transmitted by the transmission device, itis difficult to achieve high data reception quality (since thetransmission device transmits modulated signals for a plurality ofcarriers at the same time, regardless of the modulation scheme used, thePAPR is large, so the above-described conditions are important)).

Accordingly, when the transmission device illustrated in FIG. 1 is thethird transmission device (or the first transmission device), by usingthe sixth selection method, when a plurality of modulated signals aretransmitted, it is possible to increase the probability that high datareception quality can be achieved by the reception device, so performingprecoding is given as much priority as possible.

As described above, regardless of whether the transmission devicetransmits a single-carrier scheme modulated signal or a multi-carrierscheme modulated signal such as an OFDM modulated signal, the receptiondevice that receives the modulated signal transmitted by thetransmission device can achieve an advantageous effect that it ispossible to achieve an even higher data reception quality.

Next, a seventh selection method different than the fourth selectionmethod, the fifth selection method, and the sixth selection method thatis used when transmitting a multi-carrier scheme modulated signal suchas an OFDM modulated signal will be described.

Seventh Selection Method:

Transmission Method #7-1:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #7-2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #7-3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or a modulation scheme inwhich 16 signal points are in the in-phase I-quadrature Q plane, such as16APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #7-4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or a modulation scheme inwhich 64 signal points are in the in-phase I-quadrature Q plane, such as64APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #7-5

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is BPSK (or π/2 shift BPSK), and themodulation scheme of s2(i) is BPSK (or π/2 shift BPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #7-6:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is QPSK (or π/2 shift QPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #7-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)) (when θ=π/4 radians (45degrees), the average transmission power of the modulated signalstransmitted from the antennas is equal).

Transmission Method #7-8:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #7-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 16APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)). Here, θ=0 radians inEquation (13) through Equation (20) (note that θ is greater than orequal to 0 radians and less than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Note that in the seventh selection method, the transmission method neednot correspond to all transmission methods from transmission method #7-1through transmission method #7-9. For example, in the seventh selectionmethod, the transmission method may correspond to one or moretransmission method from among the following three transmission methods:transmission method #7-5, transmission method #7-6, and transmissionmethod #7-7. In the seventh transmission method, the transmission methodmay correspond to one or more transmission method from among thefollowing two transmission methods: transmission method #7-8 andtransmission method #7-9.

In the seventh selection method, the transmission method need notcorrespond to transmission method #7-1 (in the seventh selection method,the transmission method need not include transmission method #7-1 in thetransmission method selection candidates in the transmission deviceillustrated in FIG. 1 ).

The seventh selection method may include a transmission method otherthan those from transmission method #7-1 to transmission method #7-9.

Here, the following is satisfied.

Transmission Method #7-1:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #7-2:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #7-3:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #7-4:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Transmission Method #7-5:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 2 and less than or equalto 4. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #7-6:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 4 and less than or equalto 16. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #7-7:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 64. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #7-8:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 16 and less than orequal to 256. The advantageous effect of transmit diversity may beachievable.

Transmission Method #7-9:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 64 and less than orequal to 4096. The advantageous effect of transmit diversity may beachievable.

As described above, the selection method for the transmission methodwhen a single-carrier scheme modulated signal is transmitted and theselection method for the transmission method when a multi-carrier schememodulated signal such as an OFDM modulated signal is transmitted aredifferent.

The reason for why the seventh selection method is used as the selectionmethod for the transmission method when a multi-carrier scheme modulatedsignal such as an OFDM modulated signal is transmitted will bedescribed.

As a transmission device that transmits a multi-carrier scheme modulatedsignal such as an OFDM modulated signal, regardless of the modulationscheme used, it is necessary to satisfy the conditions that theinfluence of phase noise in the RF unit is small and the influence ofnon-linear distortion in the transmission power amplifier is small (whenthese conditions are not satisfied, in the reception device thatreceives the modulated signal transmitted by the transmission device, itis difficult to achieve high data reception quality (since thetransmission device transmits modulated signals for a plurality ofcarriers at the same time, regardless of the modulation scheme used, thePAPR is large, so the above-described conditions are important)).

Accordingly, when the transmission device illustrated in FIG. 1 is thethird transmission device (or the first transmission device), by usingthe seventh selection method, when a plurality of modulated signals aretransmitted, it is possible to increase the probability that high datareception quality can be achieved by the reception device, so performingprecoding is given as much priority as possible.

As described above, regardless of whether the transmission devicetransmits a single-carrier scheme modulated signal or a multi-carrierscheme modulated signal such as an OFDM modulated signal, the receptiondevice that receives the modulated signal transmitted by thetransmission device can achieve an advantageous effect that it ispossible to achieve an even higher data reception quality.

Next, an eighth selection method different than the fourth selectionmethod, the fifth selection method, the sixth selection method, and theseventh selection method that is used when transmitting a multi-carrierscheme modulated signal such as an OFDM modulated signal will bedescribed.

Eighth Selection Method:

Transmission Method #8-1

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #8-2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #8-3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or a modulation scheme inwhich 16 signal points are in the in-phase I-quadrature Q plane, such as16APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #8-4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or a modulation scheme inwhich 64 signal points are in the in-phase I-quadrature Q plane, such as64APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #8-5:

Either one of transmission method #4-5 or transmission method #6-5.

Transmission Method #8-6:

Either one of transmission method #4-6 or transmission method #6-6.

Transmission Method #8-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #8-8:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #8-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 16APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)). Here, θ=0 radians inEquation (13) through Equation (20) (note that θ is greater than orequal to 0 radians and less than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Note that in the eighth selection method, the transmission method neednot correspond to all transmission methods from transmission method #8-1through transmission method #8-9. For example, in the eighth selectionmethod, the transmission method may correspond to one or moretransmission method from among the following three transmission methods:transmission method #8-5, transmission method #8-6, and transmissionmethod #8-7. In the eighth transmission method, the transmission methodmay correspond to one or more transmission method from among thefollowing two transmission methods: transmission method #8-8 andtransmission method #8-9.

In the eighth selection method, the transmission method need notcorrespond to transmission method #8-1 (in the eighth selection method,the transmission method need not include transmission method #8-1 in thetransmission method selection candidates in the transmission deviceillustrated in FIG. 1 ).

The eighth selection method may include a transmission method other thanthose from transmission method #8-1 to transmission method #8-9.

Here, the following is satisfied.

Transmission Method #8-1:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #8-2:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #8-3:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #8-4:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Transmission Method #8-5:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 2 and less than or equalto 4. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #8-6:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 4 and less than or equalto 16. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #8-7:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 64. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #8-8:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 16 and less than or equal to 256.The advantageous effect of transmit diversity is achievable.

Transmission Method #8-9:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 64 and less than orequal to 4096. The advantageous effect of transmit diversity may beachievable.

As described above, the selection method for the transmission methodwhen a single-carrier scheme modulated signal is transmitted and theselection method for the transmission method when a multi-carrier schememodulated signal such as an OFDM modulated signal is transmitted aredifferent.

The reason for why the eighth selection method is used as the selectionmethod for the transmission method when a multi-carrier scheme modulatedsignal such as an OFDM modulated signal is transmitted will bedescribed.

As a transmission device that transmits a multi-carrier scheme modulatedsignal such as an OFDM modulated signal, regardless of the modulationscheme used, it is necessary to satisfy the conditions that theinfluence of phase noise in the RF unit is small and the influence ofnon-linear distortion in the transmission power amplifier is small (whenthese conditions are not satisfied, in the reception device thatreceives the modulated signal transmitted by the transmission device, itis difficult to achieve high data reception quality (since thetransmission device transmits modulated signals for a plurality ofcarriers at the same time, regardless of the modulation scheme used, thePAPR is large, so the above-described conditions are important)).

Accordingly, when the transmission device illustrated in FIG. 1 is thethird transmission device (or the first transmission device), by usingthe eighth selection method, when a plurality of modulated signals aretransmitted, it is possible to increase the probability that high datareception quality can be achieved by the reception device, so performingprecoding is given as much priority as possible.

As described above, regardless of whether the transmission devicetransmits a single-carrier scheme modulated signal or a multi-carrierscheme modulated signal such as an OFDM modulated signal, the receptiondevice that receives the modulated signal transmitted by thetransmission device can achieve an advantageous effect that it ispossible to achieve an even higher data reception quality.

Next, a ninth selection method different than the fourth selectionmethod, the fifth selection method, the sixth selection method, theseventh selection method, and the eighth selection method that is usedwhen transmitting a multi-carrier scheme modulated signal such as anOFDM modulated signal will be described.

Ninth Selection Method:

Transmission Method #9-1:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #9-2:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme (of s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #9-3:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or a modulation scheme inwhich 16 signal points are in the in-phase I-quadrature Q plane, such as16APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #9-4:

A single stream is transmitted (s1(i) is transmitted). The modulationscheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or a modulation scheme inwhich 64 signal points are in the in-phase I-quadrature Q plane, such as64APSK (a shift may be performed)) (however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively,transmitted using a plurality of antennas).

Transmission Method #9-5:

Either one of transmission method #4-5 or transmission method #6-5.

Transmission Method #9-6:

Either one of transmission method #4-6 or transmission method #6-6.

Transmission Method #9-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Transmission Method #9-8:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #9-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift G4QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed, coefficient multiplication is also performed (by coefficientmultipliers 301A, 302A)). Here, θ≠0 radians in Equation (13) throughEquation (20) (note that θ is greater than or equal to 0 radians andless than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 16APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)). Here, θ=0 radians inEquation (13) through Equation (20) (note that θ is greater than orequal to 0 radians and less than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed, coefficient multiplication is alsoperformed (by coefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a plurality ofprecoding matrices expressed by any of Equation (13) through Equation(20) are provided for performing precoding processing. For example, N (Nis an integer that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matrixesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 uses one matrix specified by control signal 200 fromamong the N matrices from the first matrix to the N-th matrix, andperforms precoding.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Note that in the ninth selection method, the transmission method neednot correspond to all transmission methods from transmission method #9-1to transmission method #9-9. For example, in the ninth selection method,the transmission method may correspond to one or more transmissionmethod from among the following three transmission methods: transmissionmethod #9-5, transmission method #9-6, and transmission method #9-7. Inthe ninth transmission method, the transmission method may correspond toone or more transmission method from among the following twotransmission methods: transmission method #9-8 and transmission method#9-9.

In the ninth selection method, the transmission method need notcorrespond to transmission method #9-1 (in the ninth selection method,the transmission method need not include transmission method #9-1 in thetransmission method selection candidates in the transmission deviceillustrated in FIG. 1 ).

The ninth selection method may include a transmission method other thanthose from transmission method #9-1 to transmission method #9-9.

Here, the following is satisfied.

Transmission Method #9-1:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 2.

Transmission Method #9-2:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 4.

Transmission Method #9-3:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 16.

Transmission Method #9-4:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is 64.

Transmission Method #9-5:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 2 and less than or equalto 4. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #9-6:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 4 and less than or equalto 16. There are cases in which the advantageous effect of transmitdiversity is achievable.

Transmission Method #9-7:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than 4 and less than or equal to 64. Theadvantageous effect of transmit diversity is achievable.

Transmission Method #9-8:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 16 and less than orequal to 256. The advantageous effect of transmit diversity may beachievable.

Transmission Method #9-9:

The number of signal points in the in-phase I-quadrature Q plane of thetransmission signal is greater than or equal to 64 and less than orequal to 4096. The advantageous effect of transmit diversity may beachievable.

As described above, the selection method for the transmission methodwhen a single-carrier scheme modulated signal is transmitted and theselection method for the transmission method when a multi-carrier schememodulated signal such as an OFDM modulated signal is transmitted aredifferent.

The reason for why the ninth selection method is used as the selectionmethod for the transmission method when a multi-carrier scheme modulatedsignal such as an OFDM modulated signal is transmitted will bedescribed.

As a transmission device that transmits a multi-carrier scheme modulatedsignal such as an OFDM modulated signal, regardless of the modulationscheme used, it is necessary to satisfy the conditions that theinfluence of phase noise in the RF unit is small and the influence ofnon-linear distortion in the transmission power amplifier is small (whenthese conditions are not satisfied, in the reception device thatreceives the modulated signal transmitted by the transmission device, itis difficult to achieve high data reception quality (since thetransmission device transmits modulated signals for a plurality ofcarriers at the same time, regardless of the modulation scheme used, thePAPR is large, so the above-described conditions are important)).

Accordingly, when the transmission device illustrated in FIG. 1 is thethird transmission device (or the first transmission device), by usingthe ninth selection method, when a plurality of modulated signals aretransmitted, it is possible to increase the probability that high datareception quality can be achieved by the reception device, so performingprecoding is given as much priority as possible.

As described above, regardless of whether the transmission devicetransmits a single-carrier scheme modulated signal or a multi-carrierscheme modulated signal such as an OFDM modulated signal, the receptiondevice that receives the modulated signal transmitted by thetransmission device can achieve an advantageous effect that it ispossible to achieve an even higher data reception quality.

Next, application examples will be given of a single-carriertransmission method and a multi-carrier scheme transmission method suchas an OFDM transmission method as described above.

For example, assume that communications standard α exists as a radiocommunications method. The frequency band used in communicationsstandard α is predetermined, and in communications standard α, one ormore frequency bands are set. In such cases, communications standard αis capable of both single-carrier modulated signal transmission andmulti-carrier modulated signal transmission, such as OFDM modulatedsignal transmission.

Moreover, communications standard α supports any one of the firstselection method, second selection method, or third selection methoddescribed in Embodiment 1 as single-carrier transmission, and supportsany one of the fourth selection method, fifth selection method, sixthselection method, seventh selection method, eighth selection method, orninth selection method described in this embodiment as multi-carriertransmission such as OFDM transmission.

Accordingly, based on the descriptions of the first transmission device,second transmission device, and third transmission device, the followingthree types of transmission devices can be considered.

Fourth Transmission Device:

The fourth transmission device is a transmission device capable ofselectively transmitting both a single-carrier scheme modulated signalin accordance with communications standard α and a multi-carrier schememodulated signal such as an OFDM modulated signal in accordance withcommunications standard α. Control signal 100 in the transmission deviceillustrated in FIG. 1 includes control information for specifyingtransmission using a single-carrier scheme or transmission using amulti-carrier scheme such as OFDM, and when control signal 100 indicatestransmission using a single-carrier scheme, the transmission deviceillustrated in FIG. 1 transmits a single-carrier scheme modulated signalin accordance with communications standard α, and when control signal100 indicates transmission using a multi-carrier scheme such as OFDM,the transmission device illustrated in FIG. 1 transmits a multi-carrierscheme modulated signal such as an OFDM modulated signal in accordancewith communications standard α. Note that as a result of thetransmission device illustrated in FIG. 1 transmitting, to the receptiondevice illustrated in FIG. 19 , control information for specifyingtransmission using a single-carrier scheme or transmission using amulti-carrier scheme such as OFDM, the reception device illustrated inFIG. 19 can receive, demodulate, and decode the modulated signaltransmitted by the transmission device illustrated in FIG. 1 .

Fifth Transmission Device:

The fifth transmission device is a transmission device capable oftransmitting a single-carrier scheme modulated signal in accordance withcommunications standard α. When control signal 100 in the transmissiondevice illustrated in FIG. 1 includes control information for specifyingtransmission using a single-carrier scheme or transmission using amulti-carrier scheme such as OFDM, the second transmission device canonly select transmission using a single-carrier scheme as this controlinformation. Accordingly, the transmission device illustrated in FIG. 1transmits a single-carrier scheme modulated signal in accordance withcommunications standard α. Note that as a result of the transmissiondevice illustrated in FIG. 1 transmitting, to the reception deviceillustrated in FIG. 19 , control information for specifying transmissionusing a single-carrier scheme or transmission using a multi-carrierscheme such as OFDM, the reception device illustrated in FIG. 19 canreceive, demodulate, and decode the modulated signal transmitted by thetransmission device illustrated in FIG. 1 .

Sixth Transmission Device:

The sixth transmission device is a transmission device capable oftransmitting a multi-carrier scheme modulated signal such as an OFDMmodulated signal in accordance with communications standard α. Whencontrol signal 100 in the transmission device illustrated in FIG. 1includes control information for specifying transmission using asingle-carrier scheme or transmission using a multi-carrier scheme suchas OFDM, the second transmission device can only select transmissionusing a multi-carrier scheme such as OFMD as this control information.Accordingly, the transmission device illustrated in FIG. 1 transmits amulti-carrier scheme modulated signal such as a OFDM modulated signal inaccordance with communications standard α. Note that as a result of thetransmission device illustrated in FIG. 1 transmitting, to the receptiondevice illustrated in FIG. 19 , control information for specifyingtransmission using a single-carrier scheme or transmission using amulti-carrier scheme such as OFDM, the reception device illustrated inFIG. 19 can receive, demodulate, and decode the modulated signaltransmitted by the transmission device illustrated in FIG. 1 .

When the fourth transmission device supports communications standard α,for example, transmission of a single-carrier scheme modulated signal inaccordance with single-carrier scheme and transmission of amulti-carrier scheme modulated signal such as a OFDM signal inaccordance with communications standard α correspond with a common RFunit and common transmission power amplifier in the transmission device,a RF unit and transmission power amplifier that exhibit small influenceof phase noise and non-linear distortion may be used for themulti-carrier scheme modulated signal such as a OFDM signal thatconforms to communications standard α. Accordingly, for thesingle-carrier scheme modulated signal that conforms to communicationsstandard α as well, influence of phase noise and non-linear distortionis small, and with this transmission device, regardless of whether asingle-carrier scheme demodulated signal that conforms to communicationsstandard α or a multi-carrier scheme modulated signal such as a OFDMmodulated signal that conforms to communications standard α istransmitted, the reception device has an advantageous effect that it canachieve a high data reception quality.

Another example is as follows. In the fourth transmission device, when asingle-carrier scheme modulated signal is transmitted in accordance withcommunications standard α, an RF unit and transmission power amplifierthat are dedicated for single-carrier scheme modulated signal usage areused, and when a multi-carrier scheme modulated signal such as an OFDMmodulated signal is transmitted in accordance with communicationsstandard α, an RF unit and transmission power amplifier that arededicated for multi-carrier scheme modulated signal such as OFDMmodulated signal usage are used.

Accordingly, regardless of whether a single-carrier scheme demodulatedsignal that conforms to communications standard α or a multi-carrierscheme modulated signal such as a OFDM modulated signal that conforms tocommunications standard α is transmitted by this transmission device,the reception device has an advantageous effect that it can achieve ahigh data reception quality. Moreover, when this transmission devicetransmits a single-carrier scheme modulated signal in accordance withcommunications standard α, a suitable RF unit and transmission poweramplifier can be used, which yields an advantageous effect that it ispossible to reduce power consumption.

The fifth transmission device transmits a single-carrier schememodulated signal in accordance with communications standard α. Here, asdescribed in Embodiments 1 and 2, the transmission methods that arecapable of performing transmission are limited in the selection methods,and thus, it is possible to reduce PAPR. Accordingly, it is possible toreduce the influence of phase noise and non-linear distortion, and inthe reception device that receives the modulated signal transmitted bythe transmission device, it is possible to achieve an advantageouseffect that data reception quality can be improved, and in thetransmission device, it is possible to achieve an advantageous effectthat an RF unit and transmission power amplifier that are small incircuitry scale and are low-consumption can be used.

The sixth transmission device transmits a multi-carrier scheme modulatedsignal such as an OFDM modulated signal in accordance withcommunications standard α. Here, as described in Embodiment 2, thetransmission methods that are capable of performing transmission arelimited in the selection methods, and thus, in the reception device thatreceives the modulated signal transmitted by the transmission device,there is an advantageous effect that data reception quality is improved.

As described above, in communications standard α that supports bothsingle-carrier transmission and multi-carrier transmission such as OFDMtransmission, it is important that the transmission method forsingle-carrier transmission and the transmission method formulti-carrier transmission such as OFDM transmission include differentaspects. This makes it possible to achieve the advantageous effectsdescribed above.

Note that a spread spectrum communication method may be used for thesingle-carrier scheme modulated signal, and a spread spectrumcommunication method may be used for the multi-carrier scheme modulatedsignal such as a OFDM modulated signal.

(Supplemental Information)

As a matter of course, the present disclosure may be carried out bycombining a plurality of the exemplary embodiments and other contentsdescribed herein.

Moreover, the embodiments are merely examples. For example, while a“modulation scheme, an error correction coding method (error correctioncode, code length, encode rate, etc., to be used), control information,etc.” are exemplified, it is possible to carry out the presentdisclosure with the same configuration even when other types of a“modulation scheme, an error correction coding method (error correctioncode, code length, encode rate, etc., to be used), control information,etc.” are applied.

Regarding the modulation scheme, even when a modulation scheme otherthan the modulation schemes described herein is used, it is possible tocarry out the embodiments and the other subject matter described herein.For example, amplitude phase shift keying (APSK) (such as 16APSK,64APSK, 128APSK, 256APSK, 1024APSK and 4096APSK), pulse amplitudemodulation (PAM) (such as 4PAM, 8PAM, 16PAM, 64PAM, 128PAM, 256PAM,1024PAM and 4096PAM), phase shift keying (PSK) (such as BPSK, QPSK,8PSK, 16PSK, 64PSK, 128PSK, 256PSK, 1024PSK and 4096PSK), and quadratureamplitude modulation (QAM) (such as 4QAM, 8QAM, 16QAM, 64QAM, 128QAM,256QAM, 1024QAM and 4096QAM) may be applied, or in each modulationscheme, uniform mapping or non-uniform mapping may be performed.Moreover, a method for arranging 2, 4, 8, 16, 64, 128, 256, 1024, etc.,signal points on an I-Q plane (a modulation scheme having 2, 4, 8, 16,64, 128, 256, 1024, etc., signal points) is not limited to a signalpoint arrangement method of the modulation schemes described herein.

In the present disclosure, it can be considered that the apparatus whichincludes the transmission device is a communications and broadcastapparatus, such as a broadcast station, a base station, an access point,a terminal or a mobile phone. In such cases, it can be considered thatthe apparatus that includes the reception device is a communicationapparatus such as a television, a radio, a terminal, a personalcomputer, a mobile phone, an access point, or a base station. Moreover,it can also be considered that the transmission device and receptiondevice according to the present disclosure are each a device havingcommunication functions that is formed so as to be connectable via someinterface to an apparatus for executing an application in, for example,a television, a radio, a personal computer or a mobile phone. Moreover,in this embodiment, symbols other than data symbols, such as pilotsymbols (preamble, unique word, post-amble, reference symbol, etc.) orsymbols for control information, may be arranged in any way in a frame.Here, the terms “pilot symbol” and “control information” are used, butthe naming of such symbols is not important; the functions that theyperform are.

A pilot symbol may be a known symbol that is modulated using PSKmodulation in a transceiver (alternatively, a symbol transmitted by atransmitter can be known by a receiver by the receiver being periodic),and the receiver detects, for example, frequency synchronization, timesynchronization, and a channel estimation (channel state information(CSI)) symbol (of each modulated signal) by using the symbol.

Moreover, the symbol for control information is a symbol fortransmitting information required to be transmitted to a communicationpartner in order to establish communication pertaining to anything otherthan data (such as application data) (this information is, for example,the modulation scheme, error correction encoding method, or encode rateof the error correction encoding method used in the communication, orsettings information in an upper layer).

Note that the present invention is not limited to each exemplaryembodiment, and can be carried out with various modifications. Forexample, in each embodiment, the present disclosure is described asbeing performed as a communications device. However, the presentdisclosure is not limited to this case, and this communications methodcan also be used as software.

Note that a program for executing the above-described communicationsmethod may be stored in Read Only Memory (ROM) in advance to cause aCentral Processing Unit (CPU) to operate this program.

Moreover, the program for executing the communications method may bestored in a computer-readable storage medium, the program stored in therecording medium may be recorded in RAM (Random Access Memory) in acomputer, and the computer may be caused to operate according to thisprogram.

Each configuration of each of the above-described embodiments, etc., maybe realized as a LSI (large scale integration) circuit, which istypically an integrated circuit. These integrated circuits may be formedas separate chips, or may be formed as one chip so as to include theentire configuration or part of the configuration of each embodiment.LSI is described here, but the integrated circuit may also be referredto as an IC (integrated circuit), a system LSI circuit, a super LSIcircuit or an ultra LSI circuit depending on the degree of integration.Moreover, the circuit integration technique is not limited to LSI, andmay be realized by a dedicated circuit or a general purpose processor.After manufacturing of the LSI circuit, a programmable FieldProgrammable Gate Array (FPGA) or a reconfigurable processor which isreconfigurable in connection or settings of circuit cells inside the LSIcircuit may be used. Further, when development of a semiconductortechnology or another derived technology provides a circuit integrationtechnology which replaces LSI, as a matter of course, functional blocksmay be integrated by using this technology. Adaption of biotechnology,for example, is a possibility.

Moreover, in the embodiments of the present specification, thedescription of the configuration of the transmission device was givenbased on the configuration illustrated in FIG. 1 , but the configurationof the transmission device is not limited to this example; for example,the transmission device may have the configuration illustrated in FIG.22 , and further, this may be applied to each of the embodiments.

In FIG. 22 , components that operate the same as in FIG. 1 share likereference marks. Accordingly, descriptions that overlap with, forexample, FIG. 1 will be omitted.

FIG. 22 differs in operation from FIG. 1 in that error correctionencoder 102 outputs encoded data 103_1, 103_2. For example, errorcorrection encoder 102 is a component that encodes block code such aslow density parity check (LDPC) code. Here, the 2n−1-th block encodeddata is output as encoded data 103_1, and the 2n-th block encoded datais output as encoded data 103_1 (n is an integer that is greater than orequal to 1).

Mapper 104 performs the modulation scheme mapping specified based onencoded data 103_1 to output mapped signal 105_1, and performs themodulation scheme mapping specified based on encoded data 103_2 tooutput mapped signal 105_2.

Moreover, the embodiments in the present specification described theconfiguration of signal processor 106 illustrated in FIG. 1 and FIG. 22based on the configuration illustrated in FIG. 2 , but signal processor106 may have the configuration illustrated in FIG. 23 instead of FIG. 2, and further, this may be applied to each of the embodiments.

In FIG. 23 , components that operate the same as in FIG. 2 share likereference marks. Accordingly, descriptions that overlap with, forexample, FIG. 2 will be omitted.

FIG. 23 differs from FIG. 2 in that phase changer 209B illustrated inFIG. 2 is omitted. Accordingly, baseband signal 208A corresponds tosignal-processed signal 106_A in FIG. 1 , FIG. 22 , and baseband signal208B corresponds to signal-processed signal 106_B in FIG. 1 , FIG. 22 .

In the present specification, even if the specifics of the transmissiondevice configuration are different, by generating a signal equivalent toany one of signal-processed signal 106_A, 106_B described above in anyof the embodiments of the present specification and transmitting thesignal using a plurality of antenna units, when the reception device isin an environment in which direct waves are dominant, in particular whenin an LOS environment, it is possible to achieve an advantageous effectin which the reception quality of the reception device that isperforming MIMO data symbol transferring (transfer via a plurality ofstreams) can be improved (other advantageous effects described in thepresent specification are also achievable).

Note that in signal processor 106 illustrated in FIG. 1 and FIG. 22 , aphase change may be provided both before and after weighting synthesizer203. More specifically, signal processor 106 includes, before weightingsynthesizer 203, one or both of phase changer 205A_1 that generatesphase-changed signal 2801A by applying a phase change to mapped signal201A, and phase changer 205B_1 that generates phase-changed signal 2801Bby applying a phase change to mapped signal 201B. Signal processor 106further includes, before inserter 207A, 207B, one or both of phasechanger 205A_2 that generates phase-changed signal 206A by applying aphase change to weighting synthesized signal 204A, and phase changer205B_2 that generates phase-changed signal 206B by applying a phasechange to weighting synthesized signal 204B.

Here, when signal processor 106 includes phase changer 205A_1, one inputof weighting synthesizer 203 is phase-changed signal 2801A, and whensignal processor 106 does not include phase changer 205A_1, one input ofweighting synthesizer 203 is mapped signal 201A. When signal processor106 includes phase changer 205B_1, the other input of weightingsynthesizer 203 is phase-changed signal 2801B, and when signal processor106 does not include phase changer 205B_1, the other input of weightingsynthesizer 203 is mapped signal 201B. When signal processor 106includes phase changer 205A_2, the input of inserter 207A isphase-changed signal 206A, and when signal processor 106 does notinclude phase changer 205A_2, the input of inserter 207A is weightingsynthesized signal 204A. When signal processor 106 includes phasechanger 205B_2, the input of inserter 207B is phase-changed signal 206B,and when signal processor 106 does not include phase changer 205B_2, theinput of inserter 207B is weighting synthesized signal 204B.

Moreover, the transmission device illustrated in FIG. 1 and FIG. 22 mayinclude a second signal processor that implements different signalprocessing on signal-processed signal 106_A, 106_B, i.e., the output ofsignal processor 106. Here, radio unit 107_A receives an input of signalA processed with second signal processing and performs predeterminedprocessing on the input signal, and radio unit 107_B receives an inputof signal B processed with second signal processing and performspredetermined processing on the input signal, where signal A and signalB processed with second signal processing are two signals output from asecond signal processor.

When signal processor 106 further includes, before inserter 207A, 207B,both of phase changer 205A_2 that generates phase-changed signal 206A byapplying a phase change to weighting synthesized signal 204A, and phasechanger 205B_2 that generates phase-changed signal 206B by applying aphase change to weighting synthesized signal 204B, phase-changed signals206A (z1(i)), 206B (z2(i)) input into inserters 207A, 207B can beexpressed by overwriting the following found in Equation (3) andEquation (37) through Equation (45):

[MATH.47] $\begin{matrix}{\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{with}} & \end{matrix}$ [MATH.48] $\begin{matrix}\begin{pmatrix}{y_{A}(i)} & 0 \\0 & {y_{B}(i)}\end{pmatrix} & \end{matrix}$as a first replacement. When this first replacement is made in Equation(3) and Equation (37) through Equation (45), with respect to allconfigurations described with reference to Equation (3) and Equation(37) through Equation (45) in the present specification, the resultingequations may be applied as variations.

Phase change value A(y_(A)(i)) and phase change value B(y_(B)(i)) canrespectively be expressed as y_(A)(i)=ej×δ_(A)(i) andy_(B)(i)=ej×δ_(B)(i). Here, δ_(A)(i) and δ_(B)(i) are real numbers.δ_(A)(i) and δ_(B)(i) are set such that a result of a modulo operationof the divisor 2π with respect to δ_(A)(i)−δ_(B)(i) changes in a cycle N(N is an integer that is greater than or equal to N) However, howδ_(A)(i) and δ_(B)(i) are set is not limited to this example. Forexample, a method in which phase change value A(y_(A)(i)) and phasechange value B(y_(B)(i)) each change cyclically or regularly, and thedifference (y_(A)(i)/y_(B)(i)) between phase change values A and Bchanges cyclically or regularly may be used.

When signal processor 106 does not include, before inserter 207A, 207B,either one of phase changer 205A_2 that generates phase-changed signal206A by applying a phase change to weighting synthesized signal 204A,and phase changer 205B_2 that generates phase-changed signal 206B byapplying a phase change to weighting synthesized signal 204B,phase-changed signal 206A (z1(i)) and weighting synthesized signal 204B(z2(i)) input into inserters 207A, 207B can be expressed by overwritingthe following found in Equation (3) and Equation (37) through Equation(45):

[MATH.49] $\begin{matrix}{\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{with}} & \end{matrix}$ [MATH.50] $\begin{matrix}\begin{pmatrix}{y(i)} & 0 \\0 & 1\end{pmatrix} & \end{matrix}$as a second replacement. When this second replacement is made inEquation (3) and Equation (37) through Equation (45), with respect toall configurations described with reference to Equation (3) and Equation(37) through Equation (45) in the present specification, the resultingequations may be applied as variations.

For example, phase change value y(i) is set as indicated in Equation(2). However, the method for setting phase change value y(i) is notlimited to the method used in Equation (2); for example, a method inwhich the phase is changed cyclically or regularly is conceivable.

Note that in Embodiment 1, it is described that when the modulationscheme used for mapped signal 201A (s1(i)) is QPSK and the modulationscheme used for mapped signal 201B (s2(i)) is 16QAM, the values for uand v in Equation (37) may be set as follows to achieve good datareception quality in the reception device:

$\begin{matrix}\lbrack {{MATH}.51} \rbrack & \end{matrix}$ $\begin{matrix}{{u = \sqrt{\frac{2}{3}}}\lbrack {{MATH}.52} \rbrack} & {{Equation}(51)}\end{matrix}$ $\begin{matrix}{{v = \sqrt{\frac{4}{3}}}{or}\lbrack {{MATH}.53} \rbrack} & {{Equation}(52)}\end{matrix}$ $\begin{matrix}{{u = {\alpha \times \sqrt{\frac{2}{3}}}}\lbrack {{MATH}.54} \rbrack} & {{Equation}(53)}\end{matrix}$ $\begin{matrix}{v = {\alpha \times \sqrt{\frac{4}{3}}}} & {{Equation}(54)}\end{matrix}$

However, examples of settings for the values of u and v that can achievegood data reception quality in the reception device when the modulationscheme used for mapped signal 201A (s1(i)) is QPSK and the modulationscheme used for mapped signal 201B (s2(i)) is 16QAM is not limited tothe combination of Equation (51) and Equation (52) and the combinationof Equation (53) and Equation (54).

One example will be described in which the error correction encodingscheme used by error correction encoder 102 to generate encoded data 103is selectable between a first error correction encoding scheme and asecond error correction encoding scheme that is different from the firsterror correction encoding scheme in regard to one or both of the encoderate and code length. Mapper 104 uses a first modulation scheme togenerate mapped signal 201A (s1(i)), and uses a second modulation schemedifferent from the first modulation scheme to generate mapped signal201B (s2(i)). Here, when signal processor 106 uses the first errorcorrection encoding scheme as the error correction encoding scheme anduses the first and second modulation schemes as a combination ofmodulation schemes, values u₁ and v₁ are used as the values for u and v,respectively, in Equation (37). Moreover, when signal processor 106 usesthe second error correction encoding scheme as the error correctionencoding scheme and uses the first and second modulation schemes as acombination of modulation schemes, values u₂ and v₂ are used as thevalues for u and v, respectively, in Equation (37). Here, when the ratioof u₁ and v₁ differs from the ratio of u₂ and v₂, compared to when theratio of u₁ and v₁ is the same as the ratio of u₂ and v₂, there is aprobability that the reception device can achieve good data receptionquality.

Note that in the above description, the ratio of values of u and v inEquation (37) was described as being changed when the encode rate orcode length or both of the error correction encoding scheme used byerror correction encoder 102 to generate encoded data 103 is different,but the ratio of the u and v values may be changed based on conditionsother than the encode rate or code length of the error correctionencoding scheme. For example, signal processor 106 may change the ratioof the u and v values in accordance with a combination of modulationschemes used as the first modulation scheme and the second modulationscheme. Furthermore, as one other example, even when error correctionencoding schemes are equal and the combination of modulation schemesused as the first modulation scheme and the second modulation scheme areequal, signal processor 106 may change the ratio of the values of u andv so as to differ between when a single-carrier scheme modulated signalis transmitted and a multi-carrier scheme modulated signal such as anOFDM modulated signal is transmitted. This configuration makes itpossible for reception device to achieve good data reception quality.

(Supplemental Information 2)

The fifth, sixth, seventh, eighth, and ninth selection methods describedin Embodiment 2 are described as being applied to a multi-carriertransmission method such as OFDM, but the fifth, sixth, seventh, eighth,and ninth selection methods may be applied to a single-carrier method.In other words, the transmission device may use the fifth, sixth,seventh, eighth, and ninth selection methods when generating a modulatedsignal for transmission.

The advantages of this configuration will be described next.

For example, in transmission method #7-5, transmission method #7-6,transmission method #7-8, and transmission method #7-9 in the seventhselection method, upon generating a plurality of modulated signals, thetransmission device selects a precoding matrix to be used in theprecoding from among a plurality of precoding matrices. When thetransmission device selects “a precoding matrix that satisfies any oneof Equation (13) through Equation (20) in which θ≠0”, an advantageouseffect in which data reception quality is good can be achieved when thereception field intensities of the modulated signals to be transmittedby the transmission device are different in the reception device, whichis the communication partner (each stream is transmitted from aplurality of antennas, so a spatial diversity effect can be realized).

However, when the transmission device selects “a precooling matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0”,an advantageous effect in which data reception quality is good can beachieved when the reception field intensities of the modulated signalsto be transmitted by the transmission device are not greatly differentin the reception device, which is the communication partner.

Accordingly, the transmission device can achieve an advantageous effectof improved data reception quality in the reception device, which is thecommunication partner, by suitably selecting a precoding matrix to beused when generating a plurality of modulated signals to be transmittedusing, for example, feedback information from a terminal.

Note that in the first, second, third, fourth, fifth, sixth, seventh,eighth, and ninth selection methods described in Embodiments 1 and 2,there is no need to support all of the inclusive transmission methods.Moreover, in the first, second, third, fourth, fifth, sixth, seventh,eighth, and ninth selection methods, transmission methods other than theinclusive transmission methods may be included in the group ofcandidates to be selected from by the transmission device. Moreover,both of the above may be combined.

For example, in the seventh selection method, in Embodiment 2,transmission method #7-1, transmission method #7-2, transmission method#7-3, transmission method #7-4, transmission method #7-5, transmissionmethod #7-6, transmission method #7-7, transmission method #7-8, andtransmission method #7-9 are given as transmission method candidates tobe selected from by the transmission device. Here, all transmissionmethods #7-1 through #7-9 may be included in the group of candidates tobe selected from by the transmission device. Moreover, transmissionmethods other than transmission methods #7-1 through #7-9 may beincluded in the group of candidates to be selected from by thetransmission device.

A specific example will be given.

Example 1

The group of candidates to be selected from the transmission device isset as “transmission method #7-1, transmission method #7-2, transmissionmethod #7-3, transmission method #7-4, transmission method #7-5,transmission method #7-6, transmission method #7-8, and transmissionmethod #7-9”.

Example 2

The group of candidates to be selected from the transmission device isset as “transmission method #7-1, transmission method #7-2, transmissionmethod #7-3, transmission method #7-4, transmission method #7-5,transmission method #7-6, transmission method #7-7, transmission method#7-8, transmission method #7-9, and transmission method #A”.

Transmission method #A is, for example, the following transmissionmethod.

A modulation scheme (of s1(i)) for transmitting a single stream (i.e.,for transmitting s1(i)) is 256QAM (or 256APSK (Amplitude Phase ShiftKeying) or a modulation scheme in which 256 signal points are in thein-phase I-quadratic Q plane)(however, the single stream modulatedsignal may be transmitted using a single antenna and, alternatively, maybe transmitted using a plurality of antennas).

Example 3

The group of candidates to be selected from the transmission device isset as “transmission method #7-1, transmission method #7-2, transmissionmethod #7-3, transmission method #7-4, transmission method #7-5,transmission method #7-6, transmission method #7-8, transmission method#7-9, and transmission method #A”.

Although Examples 1, 2, and 3 are provided as specific examples, theseexamples are not limiting.

Moreover, if the transmission device selects a transmission method fromamong transmission methods included in a 7′-th selection method thatincludes transmission methods #7′-1 through #7′-9, in the receptiondevice, which is the communication partner, data reception qualityimproves. 7′-th selection method:

Transmission Method #7′-1:

The modulation scheme (of s1(i)) for transmitting a single stream (i.e.,transmitting s1(i)) is BPSK (or π/2 shift BPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #7′-2:

The modulation scheme (of s1(i)) for transmitting a single stream (i.e.,transmitting s1(i)) is QPSK (or π/2 shift QPSK) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #7′-3:

The modulation scheme (of s1(i)) for transmitting a single stream (i.e.,transmitting s1(i)) is 16QAM (or π/2 shift 16QAM) (or a modulationscheme in which 16 signal points are in the in-phase I-quadrature Qplane, such as 16APSK (a shift may be performed)) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #7′-4:

The modulation scheme (of s1(i)) for transmitting a single stream (i.e.,transmitting s1(i)) is 64QAM (or π/2 shift 64QAM) (or a modulationscheme in which 64 signal points are in the in-phase I-quadrature Qplane, such as 64APSK (a shift may be performed)) (however, the singlestream modulated signal may be transmitted using a single antenna and,alternatively, transmitted using a plurality of antennas).

Transmission Method #7′-5:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is BPSK (or π/2 shift BPSK), and themodulation scheme of s2(i) is BPSK (or π/2 shift BPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed; coefficient multiplication may also be performed (bycoefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a given encode rateis set as the error correction encoding. Here, a plurality of precodingmatrices expressed by any one of Equation (13) through Equation (20) areprepared for performing precoding processes. For example, N (N is aninteger that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matricesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 performs precoding using one matrix specified by controlsignal 200 from among the N matrices from the first matrix to the N-thmatrix.

Note that the N matrices include at least one precoding matrix thatsatisfies any of Equations (13) through (20) in which θ=0, and includeat least one precoding matrix that satisfies any one of Equation (13)through Equation (20) in which θ≠0.

Transmission Method #7′-6:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is QPSK (or π/2 shift QPSK). Here, twomodulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed; coefficient multiplication may also be performed (bycoefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a given encode rateis set as the error correction encoding. Here, a plurality of precodingmatrices expressed by any of Equations (13) through (20) are preparedfor performing precoding processes. For example, N (N is an integer thatis greater than or equal to 2) precoding matrices are prepared. Here,the N precoding matrices are referred to as i-th matrix (i is an integerthat is greater than or equal to 1 and less than or equal to N) (thei-th matrix may be expressed as any one of the matrices in Equation (13)through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 performs precoding using one matrix specified by controlsignal 200 from among the N matrices from the first matrix to the N-thmatrix.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #7′-7:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is QPSK (or π/2 shift QPSK), and themodulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed; coefficient multiplication may also be performed (bycoefficient multipliers 301A, 302A)). Here, θ≠0 radians in Equation (13)through Equation (20) (note that θ is greater than or equal to 0 radiansand less than 2π radians (0 radians≤θ<2π radians)) (when θ=π/4 radians(45 degrees), the average transmission power of the modulated signalstransmitted from the antennas is equal).

Transmission Method #7′-8;

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 16QAM (or π/2 shift 16QAM) (or amodulation scheme in which 16 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed; coefficient multiplication may also be performed (bycoefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a given encode rateis set as the error correction encoding. Here, a plurality of precodingmatrices expressed by any of Equations (13) through (20) are preparedfor performing precoding processes. For example, N (N is an integer thatis greater than or equal to 2) precoding matrices are prepared. Here,the N precoding matrices are referred to as i-th matrix is an integerthat is greater than or equal to 1 and less than or equal to N) (thei-th matrix may be expressed as any one of the matrices in Equation (13)through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 performs precoding using one matrix specified by controlsignal 200 from among the N matrices from the first matrix to the N-thmatrix.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Transmission Method #7′-9:

Two streams are transmitted (s1(i) and s2(i) are transmitted). Themodulation scheme of s1(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 16APSK (a shift may be performed)), andthe modulation scheme of s2(i) is 64QAM (or π/2 shift 64QAM) (or amodulation scheme in which 64 signal points are in the in-phaseI-quadrature Q plane, such as 64APSK (a shift may be performed)). Here,two modulated signals are transmitted. The first modulated signal istransmitted using one or more antennas, and the second modulated signalis transmitted using one or more antennas. Here, based on FIG. 2 andFIG. 3 , precoding (weighted synthesis) is performed using any one ofthe (precoding) matrices in Equation (13) through Equation (20), andthereafter, a phase change is performed (by phase changer 205B), and thetwo streams are transmitted (note that a phase change need not beperformed; coefficient multiplication may also be performed (bycoefficient multipliers 301A, 302A)). Here, θ≠0 radians in Equation (13)through Equation (20) (note that θ is greater than or equal to 0 radiansand less than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 16APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed; coefficient multiplication may also beperformed (by coefficient multipliers 301A, 302A)). Here, θ=0 radians inEquation (13) through Equation (20) (note that θ is greater than orequal to 0 radians and less than 2π radians (0 radians≤θ<2π radians)).

Alternatively, two streams are transmitted (s1(i) and s2(i) aretransmitted). The modulation scheme of s1(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)), and the modulation scheme of s2(i) is 64QAM (or π/2 shift64QAM) (or a modulation scheme in which 64 signal points are in thein-phase I-quadrature Q plane, such as 64APSK (a shift may beperformed)). Here, two modulated signals are transmitted. The firstmodulated signal is transmitted using one or more antennas, and thesecond modulated signal is transmitted using one or more antennas. Here,based on FIG. 2 and FIG. 3 , precoding (weighted synthesis) is performedusing any one of the (precoding) matrices in Equation (13) throughEquation (20), and thereafter, a phase change is performed (by phasechanger 205B), and the two streams are transmitted (note that a phasechange need not be performed; coefficient multiplication may also beperformed (by coefficient multipliers 301A, 302A)).

Next, precoding processing will be described.

In the transmission device illustrated in FIG. 1 , a given encode rateis set as the error correction encoding. Here, a plurality of precodingmatrices expressed by any of Equations (13) through (20) are preparedfor performing precoding processes. For example, N (N is an integer thatis greater than or equal to 2) precoding matrices are prepared. Here,the N precoding matrices are referred to as i-th matrix (i is an integerthat is greater than or equal to 1 and less than or equal to N) (thei-th matrix may be expressed as any one of the matrices in Equation (13)through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 performs precoding using one matrix specified by controlsignal 200 from among the N matrices from the first matrix to the N-thmatrix.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0.

Note that in transmission method #7′-5, transmission method #7′-6,transmission method #7′-8, and transmission method #7′-9, “a givenencode rate is set as the error correction encoding” is stipulated, butthis is not limited to a single encode rate.

For example, when the encode rate is ½, a plurality of precodingmatrices expressed by any of Equation (13) through Equation (20) areprovided for performing precoding processing. For example, N (N is aninteger that is greater than or equal to 2) precoding matrices areprepared. Here, the N precoding matrices are referred to as i-th matrix(i is an integer that is greater than or equal to 1 and less than orequal to N) (the i-th matrix may be expressed as any one of the matricesin Equation (13) through Equation (20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 performs precoding using one matrix specified by controlsignal 200 from among the N matrices from the first matrix to the N-thmatrix.

Note that the N matrices include at least one precoding matrix thatsatisfies any one of Equation (13) through Equation (20) in which θ=0,and include at least one precoding matrix that satisfies any one ofEquation (13) through Equation (20) in which θ≠0. When the encode rateis ⅔, a plurality of precoding matrices expressed by any of Equation(13) through Equation (20) are provided for performing precodingprocessing. For example, N (N is an integer that is greater than orequal to 2) precoding matrices are prepared. Here, the N precodingmatrices are referred to as i-th matrix is an integer that is greaterthan or equal to 1 and less than or equal to N) (the i-th matrix may beexpressed as any one of the matrices in Equation (13) through Equation(20)).

Based on control signal 200, weighting synthesizer 203 illustrated inFIG. 2 , FIG. 3 performs precoding using one matrix specified by controlsignal 200 from among the N matrices from the first matrix to the N-thmatrix.

Note that the following may be adopted: the N matrices include at leastone precoding matrix that satisfies any one of Equation (13) throughEquation (20) in which θ=0, and include at least one precoding matrixthat satisfies any one of Equation (13) through Equation (20) in whichθ≠0.

Moreover, in the 7′-th selection method, there is no need to support allof the inclusive transmission methods. Moreover, in the 7′-th selectionmethod, transmission methods other than the inclusive transmissionmethods may be included in the group of candidates to be selected fromby the transmission device. Moreover, both of the above may be combined.

For example, in the 7′-th selection method, transmission method #7′-1,transmission method #7′-2, transmission method #7′-3, transmissionmethod #7′-4, transmission method #7′-5, transmission method #7′-6,transmission method #7′-7, transmission method #7′-8, and transmissionmethod #7′-9 are given as transmission method candidates to be selectedfrom by the transmission device. Here, all transmission methods #7′-1through #7′-9 may be included in the group of candidates to be selectedfrom by the transmission device. Moreover, transmission methods otherthan transmission methods #7′-1 through #7′-9 may be included in thegroup of candidates to be selected from by the transmission device.

A specific example will be given.

Example 4

Transmission method #7′-1, transmission method #7′-2, transmissionmethod #7′-3, transmission method #7′-4, transmission method #7′-5,transmission method #7′-6, transmission method #7′-8, and transmissionmethod #7′-9 are set as candidates to be selected from by thetransmission device.

Example 5

Transmission method #7′-1, transmission method #7′-2, transmissionmethod #7′-3, transmission method #7′-4, transmission method #7′-5,transmission method #7′-6, transmission method #7′-7, transmissionmethod #7′-8, transmission method #7′-9, and transmission method #A areset as candidates to be selected from by the transmission device.

Example 6

Transmission method #7′-1, transmission method #7′-2, transmissionmethod #7′-3, transmission method #7′-4, transmission method #7′-5,transmission method #7′-6, transmission method #7′-8, transmissionmethod #7′-9, and transmission method #A are set as candidates to beselected from by the transmission device.

Although Examples 4, 5, and 6 are provided as specific examples, theseexamples are not limiting.

Embodiment 3

In this embodiment, a configuration different from those in FIG. 2 andFIG. 23 of signal processor 106 in the transmission device illustratedin FIG. 1 and FIG. 22 will be described.

FIG. 24 illustrates one example of a configuration of signal processor106 different from the configurations illustrated in FIG. 2 and FIG. 23. Components that operate the same as in FIG. 2 and FIG. 23 share likereference marks. Accordingly, repeated description thereof will beomitted.

FIG. 24 differs from FIG. 2 particularly in regard to the addition oftwo phase changers directly after weighting synthesizer 203.

Phase changer 205A receives inputs of weighting synthesized signal 204Aand control signal 200, applies a phase change to weighting synthesizedsignal 204A based on control signal 200, and outputs phase-changedsignal 206A. As one example, weighting synthesized signal 204A isexpressed as z1′(t). Note that t is time, and z1′(t) is defined as acomplex number. Accordingly, z1′(t) may be a real number. Phase-changedsignal 206A is expressed as z1(t). z1(t) is defined as a complex number.Accordingly, z1(t) may be a real number. z1′(t) and z1(t) are describedas functions of t, but may be functions of frequency f, and may befunctions of both time t and frequency f. These may also be functions ofsymbol number i. Hereinafter, they will be described as functions ofsymbol number i. In regard to this point, throughout the entire presentspecification, the same description and formulaic equations are given.

Phase changer 205B receives inputs of weighting synthesized signal 204Band control signal 200, applies a phase change to weighting synthesizedsignal 204B based on control signal 200, and outputs phase-changedsignal 206B. As one example, weighting synthesized signal 204B isexpressed as z2′(t). Note that t is time, and z2′(t) is defined as acomplex number. Accordingly, z2′(t) may be a real number. Phase-changedsignal 206B is expressed as z2(t). Note that z2(t) is defined as acomplex number. Accordingly, z2(t) may be a real number. z2′(t) andz2(t) are described as functions of t, but may be functions of frequencyf, and may be functions of both time t and frequency f. These may alsobe functions of symbol number i. Hereinafter, they will be described asfunctions of symbol number i.

Weighting synthesizer (precoder) 203 performs the following calculation.

$\begin{matrix}\lbrack {{MATH}.55} \rbrack & \end{matrix}$ $\begin{matrix}{\begin{pmatrix}{z1^{\prime}(i)} \\{z2^{\prime}(i)}\end{pmatrix} = {\begin{pmatrix}a & b \\c & d\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} & {{Equation}(55)}\end{matrix}$

In Equation (55), a, b, c, and d are defined as complex numbers, and,accordingly, may be real numbers. Detailed examples of the precodingmatrix (Equation (4)) of a, b, c, and d are given in Equation (5)through Equation (36) in Embodiment 1.

In phase changer 205A, for example, a phase change of Y(i) is applied toz1′(i). Accordingly, z1(i) can be expressed as z1(i)=Y(i)×z1′(i). Notthat, for example, symbol number i is an integer that is greater than orequal to 0.

In phase changer 205B, for example, a phase change of y(i) is applied toz2′(i). Accordingly, z2(i) can be expressed as z2(i)=y(i)×z2′(i).

Accordingly, z1(i) and z2(i) can be expressed with the followingformula.

$\begin{matrix}\lbrack {{MATH}.56} \rbrack & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}{Y(i)} & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}a & b \\c & d\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}e^{j \times {\varepsilon(i)}} & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}a & b \\c & d\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix} & {{Equation}(56)}\end{matrix}$

Note that δ(i) and ε(i) are real numbers. z1(i) and z2(i) aretransmitted from the transmission device at the same time and using thesame frequency (same frequency band).

Note that δ(i) and ε(i) are real numbers. z1(i) and z2(i) aretransmitted from the transmission device at the same time and using thesame frequency (same frequency band).

$\begin{matrix}\lbrack {{MATH}.57} \rbrack & \end{matrix}$ $\begin{matrix}{{{Y(i)} = e^{j({\frac{\pi \times i}{N} + \Gamma})}}\lbrack {{MATH}.58} \rbrack} & {{Equation}(57)}\end{matrix}$ $\begin{matrix}{{y(i)} = e^{j({\frac{{- \pi} \times i}{N} + \Omega})}} & {{Equation}(58)}\end{matrix}$

Note that N is the phase change cycle, and is an integer that is greaterthan or equal to 3. In other words, the number of transmission streamsor number of transmission modulated signals is an integer that isgreater than 2. Moreover, Γ and Ω are real numbers (as a simplifiedexample, Γ and Ω are zero; however, this example is not limiting). Whenset in this manner, the peak-to-average power ratio (PAPR) of signalz1(i) and the PAPR of z2(i) are, in the case of a single-carrier scheme,the same. Accordingly, the phase noise in radio units 107_A and 108_Bin, for example, FIG. 1 and FIG. 22 , and the linear required criteriafor the transmission power unit are the same, which is advantageoussince low power consumption is easily achievable and a common radio unitconfiguration can be used (note that there is a high probability thatthe same advantageous effects can be achieved when a multi-carrierscheme such as OFDM is used as well).

Phase change values Y(i) and y(i) may be applied in the followingmanner.

$\begin{matrix}\lbrack {{MATH}.59} \rbrack & \end{matrix}$ $\begin{matrix}{{{Y(i)} = e^{j({\frac{{- \pi} \times i}{N} + \Gamma})}}\lbrack {{MATH}.60} \rbrack} & {{Equation}(59)}\end{matrix}$ $\begin{matrix}{{y(i)} = e^{j({\frac{\pi \times i}{N} + \Omega})}} & {{Equation}(60)}\end{matrix}$

Even when applied as in Equation (59) and Equation (60), the sameadvantageous effects as above can be achieved.

Phase change values Y(i) and y(i) may be applied in the followingmanner.

$\begin{matrix}\lbrack {{MATH}.61} \rbrack & \end{matrix}$ $\begin{matrix}{{{Y(i)} = e^{j({\frac{k \times \pi \times i}{N} + \Gamma})}}\lbrack {{MATH}.62} \rbrack} & {{Equation}(61)}\end{matrix}$ $\begin{matrix}{{y(i)} = {e^{j}( {\frac{{- k} \times \pi \times i}{N} + \Omega} )}} & {{Equation}(62)}\end{matrix}$

Note that k is an integer excluding 0. Even when applied as in Equation(61) and Equation (62), the same advantageous effects as above can beachieved.

Application of phase change values Y(i) and y(i) is not limited to theabove examples. When the precoding matrix used by weighting synthesizer203 in FIG. 24 is expressed as in Equation (33) and Equation (34),weighting synthesizer 203 in FIG. 24 outputs mapped signal 201A asweighting synthesized signal 204A and mapped signal 201B as weightingsynthesized signal 204B without performing signal processing on mappedsignals 201A, 201B. Stated differently, weighting synthesizer 203 may beomitted. Alternately, when weighting synthesizer 203 is provided,control for whether to perform weighting synthesis or not may bedetermined according to control signal 200.

Next, the configuration illustrated in FIG. 25 , which is different fromthose in FIG. 2 , FIG. 23 , and FIG. 24 , of signal processor 106 in thetransmission device illustrated in FIG. 1 and FIG. 22 , will bedescribed.

In FIG. 25 , components that operate the same as in FIG. 24 share likereference marks. Accordingly, repeated description thereof will beomitted. FIG. 24 and FIG. 25 differ in that phase changer 209B ispresent in FIG. 24 and omitted in FIG. 25 . This point of difference hasalready been described in the description of FIG. 23 . Accordingly,repeated description will be omitted.

Moreover, operations performed by weighting synthesizer 203 and phasechangers 205A, 205B in FIG. 25 are the same as in the description ofFIG. 24 . Accordingly, repeated description will be omitted. When theprecoding matrix used by weighting synthesizer 203 in FIG. 25 isexpressed as in Equation (33) and Equation (34), weighting synthesizer203 in FIG. 25 outputs mapped signal 201A as weighting synthesizedsignal 204A and mapped signal 201B as weighting synthesized signal 204Bwithout performing signal processing on mapped signals 201A, 201B.Stated differently, weighting synthesizer 203 may be omitted.Alternately, when weighting synthesizer 203 is provided, control forwhether to perform weighting synthesis or not may be determinedaccording to control signal 200.

The configuration of signal processor 106 in the transmission device inFIG. 1 and FIG. 22 has the configurations of FIG. 24 and FIG. 25described in this embodiment, and even if various embodiments describedin the present specification are combined with respect to transmissiondevice in FIG. 1 and FIG. 22 including the configurations in FIG. 24 andFIG. 25 , these can be implemented in the same manner as in theembodiments, and can achieve the same advantageous effects described inthe embodiments.

(Supplemental Information 3)

In this embodiment, a configuration different from those in FIG. 2 ,FIG. 23 , FIG. 24 , and FIG. 25 of signal processor 106 in thetransmission device illustrated in FIG. 1 and FIG. 22 will be described.

The configuration of signal processor 106 in the transmission device inFIG. 1 and FIG. 22 is achieved by connecting FIG. 26 or FIG. 27 or FIG.28 or FIG. 29 or FIG. 30 to FIG. 23 or FIG. 25 . Since FIG. 23 and FIG.25 have already been described, the following will focus on theconfigurations of FIG. 26 through FIG. 30 .

FIG. 26 illustrates a first configuration after inserter 207A and afterinserter 207B in FIG. 23 and FIG. 25 .

In FIG. 26 , components that operate the same as in FIG. 23 , FIG. 25share like reference marks. Accordingly, repeated description thereofwill be omitted.

Cyclic delay diversity (CDD) unit 2601A receives inputs of signal 208Aand control signal 200, implements a CDD process on signal 208A based oncontrol signal 200, and outputs CDD processed signal 2602A. Note thatCDD may be referred to as cyclic shift diversity (CSD).

CDD processed signal 2602A in FIG. 26 corresponds to processed signal106_A in FIG. 1 and FIG. 22 , and signal 208B corresponds to processedsignal 106_B in FIG. 1 and FIG. 22 .

FIG. 27 illustrates a second configuration after inserter 207A and afterinserter 207B in FIG. 23 and FIG. 25 .

In FIG. 27 , components that operate the same as in FIG. 23 , FIG. 25share like reference marks. Accordingly, repeated description thereofwill be omitted.

CDD unit 2601B receives inputs of signal 208B and control signal 200,implements a CDD process on signal 208B based on control signal 200, andoutputs CDD processed signal 2602B.

Signal 208A in FIG. 27 corresponds to processed signal 106_A in FIG. 1and FIG. 22 , and CDD processed signal 2602B corresponds to processedsignal 106_B in FIG. 1 and FIG. 22 .

FIG. 28 illustrates a third configuration after inserter 207A and afterinserter 207B in FIG. 23 and FIG. 25 .

In FIG. 28 , components that operate the same as in FIG. 23 , FIG. 25 ,FIG. 26 , and FIG. 27 share like reference marks. Accordingly, repeateddescription thereof will be omitted.

CDD processed signal 2602A in FIG. 27 corresponds to processed signal106_A in FIG. 1 and FIG. 22 , and CDD processed signal 2602B correspondsto processed signal 106B in FIG. 1 and FIG. 22 .

FIG. 29 illustrates a fourth configuration after inserter 207A and afterinserter 207B in FIG. 23 and FIG. 25 .

In FIG. 29 , components that operate the same as in FIG. 23 , FIG. 25share like reference marks. Accordingly, repeated description thereofwill be omitted.

Phase changer 209A receives inputs of signal 208A and control signal200, and based on control signal 200, applies a phase change to signal208A, and outputs phase-changed signal 210A. Note that the operationsperformed by phase changer 209A are the same as phase changer 209B inFIG. 2 . Accordingly, repeated description thereof will be omitted.

Phase-changed signal 210A in FIG. 29 corresponds to processed signal106_A in FIG. 1 and FIG. 22 , and signal 208B corresponds to processedsignal 106_B in FIG. 1 and FIG. 22 .

FIG. 30 illustrates a fifth configuration after inserter 207A and afterinserter 207B in FIG. 23 and FIG. 25 .

In FIG. 30 , components that operate the same as in FIG. 2 , FIG. 23 ,FIG. 25 , and FIG. 29 share like reference marks. Accordingly, repeateddescription thereof will be omitted.

Phase-changed signal 210A in FIG. 30 corresponds to processed signal106_A in FIG. 1 and FIG. 22 , and phase-changed signal 210B correspondsto processed signal 106_B in FIG. 1 and FIG. 22 .

The configuration of the signal processor in the transmission device inFIG. 1 and FIG. 22 has a configuration described above, and even ifvarious embodiments described in the present specification are combinedwith respect to the transmission device, these can be implemented in thesame manner as in the embodiments, and can achieve the same advantageouseffects described in the embodiments.

Next, operations performed by CDD units 2601A and 2601B, and phasechangers 209A and 209B will be described.

First, the CDD process will be described.

FIG. 31 illustrates a configuration in the case that CDD (CSD) is used.Components that perform the same processes as CDD units 2601A and 2601Bare 3102_1 through 3102_M in FIG. 31 .

Cyclic delayer 3102_1 receives an input of modulated signal 3101,applies a cyclic delay, and outputs cyclic-delayed signal 3103_1. Whencyclic-delayed signal 3103_1 is expressed as X1[n], X1[n] can be appliedwith the following equation.[MATH. 63]X1[n]=X[(n−δ1)mod N]  Equation (63)

Note that, “mod” represents “modulo”, and “y mod Z” means “remainderwhen y is divided by Z”. Note that δ1 is the cyclic delay amount (δ1 isan integer), and x[n] is configured as N samples (N is an integer thatis greater than or equal to 2). Accordingly, n is an integer that isgreater than or equal to 0 and less than or equal to N−1.

Cyclic delayer 3102_M receives an input of modulated signal 3101,applies a cyclic delay, and outputs cyclic-delayed signal 3103_M. Whencyclic-delayed signal 3103_M is expressed as XM[n], XM[n] can be appliedwith the following equation.[MATH. 64]XM[n]=X[(nδM)mod N]  Equation (64)

Note that δM is the cyclic delay amount (δM is an integer), and X[n] isconfigured as N samples (N is an integer that is greater than or equalto 2). Accordingly, n is an integer that is greater than or equal to 0and less than or equal to N−1.

Cyclic delayer 3102_i (i is an integer that is greater than or equal to1 and less than or equal to M (M is an integer that is greater than orequal to 1)) receives an input of modulated signal 3101, applies acyclic delay, and outputs cyclic-delayed signal 3103_i. Whencyclic-delayed signal 3103_i is expressed as Xi[n], Xi[n] can be appliedwith the following equation.[MATH. 65]Xi[n]=X[(n−δi)mod N]  Equation (65)

Note that δi is the cyclic delay amount (δi is an integer), and X[n] isconfigured as N samples (N is an integer that is greater than or equalto 2). Accordingly, n is an integer that is greater than or equal to 0and less than or equal to N−1.

Cyclic-delayed signal 3103_i is transmitted from antenna i. Accordingly,cyclic-delayed signal 3103_1, . . . , and cyclic-delayed signal 3103_Mare each transmitted from different antennas.

This makes it possible to achieve the diversity effect via cyclic delay(in particular, reduce the adverse effects of delayed radio waves), andin the reception device, achieve an advantageous effect of improved datareception quality.

Next, the relationship between CDD units 2601A and 2601B and phasechangers 209A and 209B will be described.

For example, consider a case in which CDD (CSD) is applied to OFDM.

Assume the carrier of the lowest frequency is “carrier 1”, andsubsequent carriers are “carrier 2”, “carrier 3”, “carrier 4”, . . . .

For example, in phase changers 209A and 209B, CDD units 2601A and 2601Bapply a cyclic delay amount τ. In such as case, phase change value Ω[i]in “carrier i” can be expressed as follows.[MATH. 66]Ω[i]e ^(j×μ×i)  Equation (66)

Note that μ is a value capable of being calculated from cyclic delayamount and/or the size of the fast Fourier transform (FFT).

When the baseband signal for “carrier i”, time t before being appliedwith a phase change (before cyclic delay processing) is expressed asv′[i][t], the signal v[i][t] for “carrier i”, time t after being appliedwith a phase change can be expressed as v[i][t]=Ω[i]×v′[i][t].

Accordingly, even if a cyclic delay amount is applied, phase changers209A and 209B perform phase-change operations.

In phase changers 205A and 205B in, for example, FIG. 2 , FIG. 23 , FIG.24 , and FIG. 25 , control for whether to apply a phase change or notmay be performed via the input control signal 200. Accordingly, forexample, control signal 200 may include control information regarding“apply or do not apply a phase change in phase changer 205A” and controlinformation regarding “apply or do not apply a phase change in phasechanger 205B”, and based on this control information, control of whetherto “apply or do not apply a phase change in phase changer 205A and phasechanger 205B” may be performed.

Phase changer 205A receives an input of control signal 200, and when aphase change is not to be implemented, as indicated by control signal200, phase changer 205A outputs input signal 204A as 206A.

Similarly, phase changer 205B receives an input of control signal 200,and when a phase change is not to be implemented, as indicated bycontrol signal 200, phase changer 205B outputs input signal 204B as206B.

Note that since the transmission device notifies the reception device,which is the communication partner, of the information in phase changers205A and 205B related to “whether to implement a phase change or not”,transmission is performed as part of a control information symbol.

Moreover, in FIG. 2 , FIG. 24 , FIG. 26 , FIG. 27 , FIG. 28 , FIG. 29 ,and FIG. 30 , in phase changers 209A and 209B and CDD units 2601A and2601B, control of whether to implement a phase change or not based onthe input control signal 200 may be performed, and control of whether toimplement CSD processing or not based on the input control signal 200may be performed. Accordingly, for example, control signal 200 mayinclude control information related to performing a phase change or notin phase changer 205A, control information related to performing a phasechange or not in phase changer 205B, control information related toperforming CDD processing or not in CDD unit 2601A, and controlinformation related to performing CDD processing or not in CDD unit2601B, and based on this control information, may control whether toimplement a phase change or not in phase changer 209A and phase changer209B and whether to implement CDD processing or not in CDD unit 2601Aand CDD unit 2601B.

Phase changer 209A receives an input of control signal 200, and when aphase change is not to be implemented, as indicated by control signal200, phase changer 209A outputs input signal 208A as 210A.

Similarly, phase changer 209B receives an input of control signal 200,and when a phase change is not to be implemented, as indicated bycontrol signal 200, phase changer 209B outputs input signal 208B as210B.

CDD unit 2601A receives an input of control signal 200, and when CDDprocessing is not to be implemented, as indicated by control signal 200,CDD unit 2601A outputs input signal 208A as 2602A.

Similarly, CDD unit 2601B receives an input of control signal 200, andwhen CDD processing is not to be implemented, as indicated by controlsignal 200, CDD unit 2601B outputs input signal 208B as 2602B.

In the present disclosure, when there is a complex plane, for example,the phase unit such as an argument is “radian”.

When the complex plane is used, display in a polar form can be made asdisplay by polar coordinates of a complex number. When point (a,b) onthe complex plane is associated with complex number z=a+jb (a and b areboth real numbers, and j is a unit of an imaginary number), and whenthis point is expressed by [r, θ] in polar coordinates, a=r×cos θ andb=r×sin θ,[MATH. 67]r=√{square root over (a ² +b ²)}  Equation (67)holds true, and r is an absolute value of z (r=|z|), and θ is anargument. Then, z=a+jb is expressed by r×ejθ.(Supplemental Information 4)

Supplemental information regarding the description of FIG. 3 given inEmbodiment 1 will be given.

Cases in which the modulation scheme used for mapped signal 201A (s1(i))is QPSK (quadrature phase shift keying) and the modulation scheme usedfor mapped signal 201B (s2(i)) is 16QAM (QAM; quadrature amplitudemodulation) will be described.

Note that here, the average (transmission) power of mapped signal 201Aand the average (transmission) power of mapped signal 201B are the same.

In the description of FIG. 3 in Embodiment 1, operations performed whenphase changer 205B is provided are described, but when phase changer205B does not implement a phase change, or when phase changer 205B isomitted, there is a method that can improve data reception quality. Thiswill be discussed below.

Weighting synthesized signal 204A (Z1(i)) and the signal when a phasechange is not implemented are z2(i) (this corresponds to 204B; however,204B and 206B are the same signal). Here, based on FIG. 4 , z2(i), i.e.,weighting synthesized signal 204A (Z1(i)) and the signal when a phasechange is not implemented, may be expressed by any of Equations (68)through (75). Note that F, u, v, β, θ, and the like are as described inEmbodiment 1.

$\begin{matrix}{\lbrack {{MATH}.68} \rbrack} & \end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{3}} & 0 \\0 & \sqrt{\frac{4}{3}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.69} \rbrack} & {{Equation}(68)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{4}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.70} \rbrack} & {{Equation}(69)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{3}} & 0 \\0 & \sqrt{\frac{4}{3}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.71} \rbrack} & {{Equation}(70)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{4}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.72} \rbrack} & {{Equation}(71)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{3}} & 0 \\0 & \sqrt{\frac{4}{3}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.73} \rbrack} & {{Equation}(72)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{4}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.74} \rbrack} & {{Equation}(73)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{3}} & 0 \\0 & \sqrt{\frac{4}{3}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.75} \rbrack} & {{Equation}(74)}\end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{4}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix} & {{Equation}(75)}\end{matrix}$

Note that the modulation scheme used for mapped signal 201A (s1(i)) maybe 16QAM, and the modulation scheme used for mapped signal 201B (s2(i))may be QPSK.

Note that here, the average (transmission) power of mapped signal 201Aand the average (transmission) power of mapped signal 201B are the same.

Here, based on FIG. 4 , weighting synthesized signal 204A (z1(i)) andphase-changed signal 206B (z2(i)) in FIG. 3 can be expressed with any ofEquations (76) through (83). Note that F, u, v, β, θ, and the like areas described in Embodiment 1.

$\begin{matrix}{\lbrack {{MATH}.76} \rbrack} & \end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{4}{3}} & 0 \\0 & \sqrt{\frac{2}{3}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix} & {{Equation}(76)}\end{matrix}$ [MATH.77] $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{\alpha \times \sqrt{\frac{4}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{2}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix} & {{Equations}(77)}\end{matrix}$ [MATH.78] $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{4}{3}} & 0 \\0 & \sqrt{\frac{2}{3}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.79} \rbrack} & {{Equations}(78)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{4}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{2}{3}}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.80} \rbrack} & {{Equations}(79)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}\sqrt{\frac{4}{3}} & 0 \\0 & \sqrt{\frac{2}{3}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix}\lbrack {{MATH}.81} \rbrack} & {{Equations}(80)}\end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{\alpha \times \sqrt{\frac{4}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{2}{3}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix} & {{Equations}(81)}\end{matrix}$ [MATH.82] $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{4}{3}} & 0 \\0 & \sqrt{\frac{2}{3}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.83} \rbrack} & {{Equation}(82)}\end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{4}{3}}} & 0 \\0 & {\alpha \times \sqrt{\frac{2}{3}}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix} & {{Equation}(83)}\end{matrix}$

The modulation scheme used for mapped signal 201A (s1(i)) may be 16QAM,and the modulation scheme used for mapped signal 201B (s2(i)) may be64QAM.

Note that here, the average (transmission) power of mapped signal 201Aand the average (transmission) power of mapped signal 201B are the same.

Accordingly, weighting synthesized signal 204A (z1(i)) and phase-changedsignal 206B (z2(i)) in FIG. 3 can be expressed with any of Equations(84) through (91). Note that F, u, v, β, θ, and the like are asdescribed in Embodiment 1.

$\begin{matrix}\lbrack {{MATH}.84} \rbrack & \end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{5}} & 0 \\0 & \sqrt{\frac{3}{5}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.85} \rbrack} & {{Equation}(84)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{a \times \sqrt{\frac{2}{5}}} & 0 \\0 & {a \times \sqrt{\frac{3}{5}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix}\lbrack {{MATH}.86} \rbrack} & {{Equation}(85)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{5}} & 0 \\0 & \sqrt{\frac{3}{5}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.87} \rbrack} & {{Equation}(86)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{3}{5}}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.88} \rbrack} & {{Equation}(87)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{5}} & 0 \\0 & \sqrt{\frac{3}{5}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.89} \rbrack} & {{Equation}(88)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{3}{5}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix}\lbrack {{MATH}.90} \rbrack} & {{Equation}(89)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{5}} & 0 \\0 & \sqrt{\frac{3}{5}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.91} \rbrack} & {{Equation}(90)}\end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{3}{5}}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix} & {{Equation}(91)}\end{matrix}$

FIG. 32 illustrates capacities in each of a plurality of SNRs(signal-to-noise power ratios) on a chart whereP_(16QAM)/(P_(16QAM)+P_(64QAM)) is represented on the horizontal axisand capacity is represented on the vertical axis. Here, P16QAM indicatesthe average (transmission) power of 16QAM, P64QAM indicates the average(transmission) power of 64QAM (note that the channel model in the chartis a AWGN (additive white Gaussian noise) environment). As can be seenfrom the results, by using the settings illustrated in Equation (84)through Equation (91), the reception device can achieve an advantageouseffect of good data reception quality. Note that in FIG. 32 , the 21line graphs indicating relationships between power ratio and capacitycorrespond to, in ascending order of capacity, SNR=0 dB, 1 dB, 2 dB . .. 20 dB.

The modulation scheme used for mapped signal 201A (s1(i)) may be 64QAM,and the modulation scheme used for mapped signal 201B (s2(i)) may be16QAM.

Note that here, the average (transmission) power of mapped signal 201Aand the average (transmission) power of mapped signal 201B are the same.

Accordingly, based on FIG. 32 , weighting synthesized signal 204A(z1(i)) and phase-changed signal 206B (z2(i)) in FIG. 3 can be expressedwith any of Equations (92) through (99). Note that F, u, v, β, θ, andthe like are as described in Embodiment 1.

$\begin{matrix}{\lbrack {{MATH}.92} \rbrack} & \end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{3}{5}} & 0 \\0 & \sqrt{\frac{2}{5}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.93} \rbrack} & {{Equation}(92)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{\alpha \times \sqrt{\frac{3}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{2}{5}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix}\lbrack {{MATH}.94} \rbrack} & {{Equation}(93)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{3}{5}} & 0 \\0 & \sqrt{\frac{2}{5}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.95} \rbrack} & {{Equation}(94)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{3}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{2}{5}}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.96} \rbrack} & {{Equation}(95)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= \begin{matrix}{\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{3}{5}} & 0 \\0 & \sqrt{\frac{2}{5}}\end{pmatrix}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}}\end{matrix}\lbrack {{MATH}.97} \rbrack} & {{Equation}(96)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}}} \\{\begin{pmatrix}{\alpha \times \sqrt{\frac{3}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{2}{5}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}\end{matrix}\lbrack {{MATH}.98} \rbrack} & {{Equation}(97)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{3}{5}} & 0 \\0 & \sqrt{\frac{2}{5}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.99} \rbrack} & {{Equation}(98)}\end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}1 & 0 \\0 & e^{j \times {\delta(i)}}\end{pmatrix}\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{3}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{2}{5}}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix} & {{Equation}(99)}\end{matrix}$

When the modulation scheme used for mapped signal 201A (s1(i)) is 16QAMand when the modulation scheme used for mapped signal 201B (s2(i)) is64QAM, an example of operations performed when phase changer 205B isprovided is given in the description of FIG. 3 in Embodiment 1, but whenphase changer 205B does not implement a phase change, or when phasechanger 205B is omitted, there is a method that can improve datareception quality. This will be discussed below.

Weighting synthesized signal 204A (Z1(i)) and the signal when a phasechange is not implemented are z2(i) (this corresponds to 204B; however,204B and 206B are the same signal). Here, based on FIG. 32 , z2(i),i.e., weighting synthesized signal 204A (Z1(i)) and the signal when aphase change is not implemented, may be expressed by any of Equations(100) through (107). Note that F, u, v, β, θ, and the like are asdescribed in Embodiment 1.

Note that here, the average (transmission) power of mapped signal 201Aand the average (transmission) power of mapped signal 201B are the same.

$\begin{matrix}{\lbrack {{MATH}.100} \rbrack} & \end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{5}} & 0 \\0 & \sqrt{\frac{3}{5}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.101} \rbrack} & {{Equation}(100)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\theta} & {{- \beta} \times \sin\theta} \\{\beta \times \sin\theta} & {\beta \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {{- \beta} \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {\beta \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{3}{5}}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.102} \rbrack} & {{Equation}(101)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{5}} & 0 \\0 & \sqrt{\frac{3}{5}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.103} \rbrack} & {{Equation}(102)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\theta} & {{- \sin}\theta} \\{\sin\theta} & {\cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\frac{\pi}{4}} & {{- \sin}\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {\cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{3}{5}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.104} \rbrack} & {{Equation}(103)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{5}} & 0 \\0 & \sqrt{\frac{3}{5}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.105} \rbrack} & {{Equation}(104)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\theta} & {\beta \times \sin\theta} \\{\beta \times \sin\theta} & {{- \beta} \times \cos\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\beta \times \cos\frac{\pi}{4}} & {\beta \times \sin\frac{\pi}{4}} \\{\beta \times \sin\frac{\pi}{4}} & {{- \beta} \times \cos\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{3}{5}}}\end{pmatrix}}} \\\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}\end{matrix}\lbrack {{MATH}.106} \rbrack} & {{Equation}(105)}\end{matrix}$ $\begin{matrix}{\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}\sqrt{\frac{2}{5}} & 0 \\0 & \sqrt{\frac{3}{5}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix}\lbrack {{MATH}.107} \rbrack} & {{Equation}(106)}\end{matrix}$ $\begin{matrix}\begin{matrix}{\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {{F\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\theta} & {\sin\theta} \\{\sin\theta} & {{- \cos}\theta}\end{pmatrix}\begin{pmatrix}u & 0 \\0 & v\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}} \\{= {\begin{pmatrix}{\cos\frac{\pi}{4}} & {\sin\frac{\pi}{4}} \\{\sin\frac{\pi}{4}} & {{- \cos}\frac{\pi}{4}}\end{pmatrix}\begin{pmatrix}{\alpha \times \sqrt{\frac{2}{5}}} & 0 \\0 & {\alpha \times \sqrt{\frac{3}{5}}}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}}\end{matrix} & {{Equation}(107)}\end{matrix}$

Note that in Equation (68) through Equation (107), a and 6 may be realnumbers and, alternatively, may be imaginary numbers.

In Equation (68) through Equation (107), θ is set to π/4 radians (45degrees). The average (transmission) power of coefficient multipliedsignal 302A and the average (transmission) power of coefficientmultiplied signal 302B are different, but by setting θ to π/4 radians(45 degrees), the average (transmission) power of weighting synthesizedsignal 204A (z1(i)) and the average (transmission) power of signal 206B(204B) (z2(i)) can be made to be the same, so when the transmissionrules stipulate a condition that the average transmission power of eachmodulated signal transmitted from the antennas be the same, it isnecessary to set θ to π/4 radians (45 degrees). Note that, here, θ isset to π/4 radians (45 degrees), but 0 may be set to any one of: π/4radians (45 degrees); (3×π)/4 radians (135 degrees); (5×π)/4 radians(225 degrees); and (7×π)/4 radians (315 degrees).

Moreover, the coefficients u, v are set as illustrated in Equation (68)through Equation (107).

Note that symbols (for example, z1(i), z2(i)) are described as beinggenerated using the methods exemplified in FIG. 1 , FIG. 2 , FIG. 3 ,and Equation (1) through Equation (45). In such cases, the generatedsymbols may be arranged along the time axis. When a multi-carrier schemesuch as OFDM (orthogonal frequency division multiplexing) is used, thegenerated symbols may be arranged along the frequency axis and may bearranged along the time and frequency axes. Moreover, the generatedsymbols may be interleaved (i.e., rearranged) and arranged along thetime axis, along the frequency axis, and along the time and frequencyaxes. However, z1(i) and z2(i), which are both symbol number i, aretransmitted from the transmission device at the same time and using thesame frequency (same frequency band).

Moreover, in FIG. 3 , phase changer 205A may be provided betweenweighting synthesizer 203 and inserter 207A. Accordingly, a phase changemay be applied to weighting synthesized signal 204A.

Moreover, phase changer 209A may be disposed after inserter 207A.Moreover, phase changer 209B may be omitted.

By implementing the above, since weight synthesis and power change isperformed so as to increase capacity, an advantageous effect wherebydata reception quality by the reception device, which is thecommunication partner, can be improved. Note that when the modulationschemes used for s1(i) and s2(i) are changed not in association with aframe or time, more suitable power values u, v are set.

Note that in the above example, when the modulation scheme used formapped signal 201A (s1(i)) is 16QAM and the modulation scheme used formapped signal 201B (s2(i)) is 64QAM, weighting synthesized signal 204A(z1(i) and weighting synthesized signal 206B (z2(i)) are described asbeing expressible by any of Equations (84) through (91) and (100)through (107), but via the encoding method for the error correction codeused in the generation of data included in mapped signal 201A (s1(i))and mapped signal 201B (s2(i)), the values for u and v may be changed inEquations (84) through (91) and (100) through (107). For example, assumethat there is a first error correction code and a second errorcorrection code, where the code length (block length) of the first errorcorrection code is A (A is an integer that is greater than or equal to2), and the code length (block length) of the second error correctioncode is B (B is an integer that is greater than or equal to 2). Here,A≠B.

Here, when the first error correction code is used, the value of u is uaand the value of v is va in Equations (84) through (91) and (100)through (107), and when the second error correction code is used, thevalue of u is ub and the value of v is vb in Equations (84) through (91)and (100) through (107). Here, Equation (108) holds true.

$\begin{matrix}\lbrack {{MATH}.108} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{a}}{u_{a} + v_{a}} \neq \frac{u_{b}}{u_{b} + v_{b}}} & {{Equation}(108)}\end{matrix}$

In another example, assume there is a third error correction code and afourth error correction code, where the encode rate of the third errorcorrection code is C (C is a real number greater than 0 and less than 1)and the encode rate of the fourth error correction code is D (D is areal number greater than 0 and less than 1). Here, C≠D. Here, when thethird error correction code is used, the value of u is uc and the valueof v is vc in Equations (84) through (91) and (100) through (107), andwhen the fourth error correction code is used, the value of u is ud andthe value of v is vd in Equations (84) through (91) and (100) through(107). Here, Equation (109) holds true.

$\begin{matrix}\lbrack {{MATH}.109} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{c}}{u_{c} + v_{c}} \neq \frac{u_{d}}{u_{d} + v_{d}}} & {{Equation}(109)}\end{matrix}$

In yet another example, assume there is a fifth error correction code inwhich the error correction encoding method is E and a sixth errorcorrection code in which the error correction encoding method is F. Notethat the error correction encoding method E and the error correctionencoding method F are different methods.

Here, when the fifth error correction code is used, the value of u is ueand the value of v is ve in Equations (84) through (91) and (100)through (107), and when the sixth error correction code is used, thevalue of u is of and the value of v is of in Equations (84) through (91)and (100) through (107). Here, Equation (110) holds true.

$\begin{matrix}\lbrack {{MATH}.110} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{e}}{u_{e} + v_{e}} \neq \frac{u_{f}}{u_{f} + v_{f}}} & {{Equation}(110)}\end{matrix}$

Note that in the above example, when the modulation scheme used formapped signal 201A (s1(i)) is 64QAM and the modulation scheme used formapped signal 201B (s2(i)) is 16QAM, weighting synthesized signal 204A(z1(i) and weighting synthesized signal 206B (z2(i)) are described asbeing expressible by any of Equations (92) through (99), but via theencoding method for the error correction code used in the generation ofdata included in mapped signal 201A (s1(i)) and mapped signal 201B(s2(i)), the values for u and v may be changed in Equations (92) through(99).

For example, assume that there is a first error correction code and asecond error correction code, where the code length (block length) ofthe first error correction code is G (G is an integer that is greaterthan or equal to 2), and the code length (block length) of the seconderror correction code is H (H is an integer that is greater than orequal to 2). Here, G≠H.

Here, when the first error correction code is used, the value of u is ugand the value of v is vg in Equations (92) through (99), and when thesecond error correction code is used, the value of u is uh and the valueof v is vh in Equations (92) through (99). Here, Equation (111) holdstrue.

$\begin{matrix}\lbrack {{MATH}.111} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{g}}{u_{g} + v_{g}} \neq \frac{u_{h}}{u_{h} + v_{h}}} & {{Equation}(111)}\end{matrix}$

In another example, assume there is a third error correction code and afourth error correction code, where the encode rate of the third errorcorrection code is I (I is a real number greater than 0 and less than 1)and the encode rate of the fourth error correction code is J (J is areal number greater than 0 and less than 1). Note that I≠J. Here, whenthe third error correction code is used, the value of u is ui and thevalue of v is vi in Equations (92) through (99), and when the fourtherror correction code is used, the value of u is uj and the value of vis vj in Equations (92) through (99). Here, Equation (112) holds true.

$\begin{matrix}\lbrack {{MATH}.112} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{i}}{u_{i} + v_{i}} \neq \frac{u_{j}}{u_{j} + v_{j}}} & {{Equation}(112)}\end{matrix}$

In yet another example, assume there is a fifth error correction code inwhich the error correction encoding method is K and a sixth errorcorrection code in which the error correction encoding method is M. Notethat the error correction encoding method K and the error correctionencoding method M are different methods.

Here, when the fifth error correction code is used, the value of u is ukand the value of v is vk in Equations (92) through (99), and when thesixth error correction code is used, the value of u is um and the valueof v is vm in Equations (92) through (99). Here, Equation (113) holdstrue.

$\begin{matrix}\lbrack {{MATH}.113} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{k}}{u_{k} + v_{k}} \neq \frac{u_{m}}{u_{m} + v_{m}}} & {{Equation}(113)}\end{matrix}$

Note that in the above example, when the modulation scheme used formapped signal 201A (s1(i)) is 16QAM and the modulation scheme used formapped signal 201B (s2(i)) is 64QAM, weighting synthesized signal 204A(z1(i) and weighting synthesized signal 206B (z2(i)) are described asbeing expressible by any of Equations (84) through (91) and (100)through (107), but via the encoding method for the error correction codeused in the generation of data included in mapped signal 201A (s1(i))and mapped signal 201B (s2(i)), the values for u and v may be changed inEquations (84) through (91) and (100) through (107).

For example, as a first case, error correction encoding method N is usedin mapped signal 201A (s1(i)), and error correction encoding method P isused in mapped signal 201B (s2(i)). As a second case, error correctionencoding method Q is used in mapped signal 201A (s1(i)), and errorcorrection encoding method R is used in mapped signal 201B (s2(i)).

Note that error correction encoding method N and error correctionencoding method Q are different methods, and error correction encodingmethod P and error correction encoding method R are different methodsholds true.

Here, in the first case, the value of u is un and the value of v is vnin Equations (84) through (91) and Equations (100) through (107), and inthe second case, the value of u is up and the value of v is vp inEquations (84) through (91) and Equations (100) through (107). Here,Equation (114) holds true.

$\begin{matrix}\lbrack {{MATH}.114} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{n}}{u_{n} + v_{n}} \neq \frac{u_{p}}{u_{p} + v_{p}}} & {{Equation}(114)}\end{matrix}$

Note that in the above example, when the modulation scheme used formapped signal 201A (s1(i)) is 64QAM and the modulation scheme used formapped signal 201B (s2(i)) is 16QAM, weighting synthesized signal 204A(z1(i) and weighting synthesized signal 206B (z2(i)) are described asbeing expressible by any of Equations (92) through (99), but via theencoding method for the error correction code used in the generation ofdata included in mapped signal 201A (s1(i)) and mapped signal 201B(s2(i)), the values for u and v may be changed in Equations (92) through(99).

For example, as a third case, error correction encoding method S is usedin mapped signal 201A (s1(i)), and error correction encoding method T isused in mapped signal 201B (s2(i)). As a fourth case, error correctionencoding method W is used in mapped signal 201A (s1(i)), and errorcorrection encoding method X is used in mapped signal 201B (s2(i)).

Note that error correction encoding method S and error correctionencoding method W are different methods, and error correction encodingmethod T and error correction encoding method X are different methodsholds true.

Here, in the first case, the value of u is us and the value of v is vsin Equations (92) through (99), and in the second case, the value of uis uw and the value of v is vw in Equations (92) through (99). Here,Equation (115) holds true.

$\begin{matrix}\lbrack {{MATH}.115} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{s}}{u_{s} + v_{s}} \neq \frac{u_{w}}{u_{w} + v_{w}}} & {{Equation}(115)}\end{matrix}$

Note that in the above description, when the Y-th error correctionencoding method and the Z-th error correction encoding method aredifferent, conceivable examples include the error correction encodingmethod themselves being different, the code lengths (block lengths)being different, and the encode rates being different.

In the above description, examples including the conditions “when themodulation scheme used for mapped signal 201A (s1(i)) is 16QAM, and themodulation scheme used for mapped signal 201B (s2(i)) is 64QAM” and“when the modulation scheme used for mapped signal 201A (s1(i)) is64QAM, and the modulation scheme used for mapped signal 201B (s2(i)) is16QAM”, but the sets of modulation schemes used for mapped signal 201A(s1(i)) and mapped signal 201B (s2(i)) are not limited to theseexamples.

In the above examples, when the modulation scheme used for mapped signal201A (s1(i)) is 16QAM, and the modulation scheme used for mapped signal201B (s2(i)) is non-uniform 64QAM, weighting synthesized signal 204A(z1(i) and weighting synthesized signal 206B (z2(i)) may be expressedusing any of Equations (84) through (91) and (100) through (107).

Then, in the fifth case, a first non-uniform 64QAM mapping is used, andin the sixth case, a second non-uniform 64QAM mapping is used. Note thatthe first non-uniform 64QAM mapping and the second non-uniform 64QAMmapping are different.

Here, when the first non-uniform 64QAM is used, the value of u is u1 andthe value of v is v1 in Equations (84) through (91) and (100) through(107), and when the second non-uniform 64QAM is used, the value of u isu2 and the value of v is v2 in Equations (84) through (91) and (100)through (107). Here, Equation (116) holds true.

$\begin{matrix}\lbrack {{MATH}.116} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{1}}{u_{1} + v_{1}} \neq \frac{u_{2}}{u_{2} + v_{2}}} & {{Equation}(116)}\end{matrix}$

Note that in this example, the modulation scheme used for mapped signal201A (s1(i)) may be a modulation scheme other than 16QAM.

In another example, when the modulation scheme used for mapped signal201A (s1(i)) is non-uniform 64QAM, and the modulation scheme used formapped signal 201B (s2(i)) is 16QAM, weighting synthesized signal 204A(z1(i) and weighting synthesized signal 206B (z2(i)) may be expressedusing any of Equations (92) through (99).

Then, in the seventh case, a third non-uniform 64QAM mapping is used,and in the eighth case, a fourth non-uniform 64QAM mapping is used. Notethat the third non-uniform 64QAM mapping and the fourth non-uniform64QAM mapping are different.

Here, when the third non-uniform 64QAM is used, the value of u is u3 andthe value of v is v3 in Equations (92) through (99), and when the fourthnon-uniform 64QAM is used, the value of u is u4 and the value of v is v4in Equations (92) through (99). Here, Equation (117) holds true.

$\begin{matrix}\lbrack {{MATH}.117} \rbrack & \end{matrix}$ $\begin{matrix}{\frac{u_{3}}{u_{3} + v_{3}} \neq \frac{u_{4}}{u_{4} + v_{4}}} & {{Equation}(117)}\end{matrix}$

Note that in this example, the modulation scheme used for mapped signal201B (s2(i)) may be a modulation scheme other than 16QAM.

This makes it possible to achieve an advantageous effect that thereception device can achieve a high data reception quality.

(Other Variations, etc.)

Note that in the present specification, processed signal 106_Aillustrated in, for example, FIG. 1 and FIG. 22 may be transmitted froma plurality of antennas, and processed signal 106_B illustrated in, forexample, FIG. 1 and FIG. 22 may be transmitted from a plurality ofantennas. Note that a configuration in which processed signal 106_Aincludes any one of, for example, signals 204A, 206A, 208A, 210A, and2602A is conceivable. Moreover, a configuration in which processedsignal 106_B includes any one of, for example, signals 204B, 206B, 208B,210B, and 2602B is conceivable.

For example, assume there are N transmitting antennas, i.e.,transmitting antennas 1 through N are provided. Note that N is aninteger that is greater than or equal to 2. Here, the modulated signaltransmitted from transmitting antenna k is expressed as ck. Note that kis an integer that is greater than or equal to 1 and less than or equalto N. Moreover, assume that vector C including c1 through cN isexpressed as C=(c1, c2 . . . cN)^(T). Note that transposed vector A isexpressed as A^(T). Here, when the precoding matrix (weighting matrix)is G, the following equation holds true.

$\begin{matrix}\lbrack {{MATH}.118} \rbrack & \end{matrix}$ $\begin{matrix}{C = {{G\begin{pmatrix}{d_{a}(i)} \\{d_{b}(i)}\end{pmatrix}}^{}}^{}} & {{Equation} (118 )}\end{matrix}$

Note that da(i) is processed signal 106_A, db(i) is processed signal106_B, and i is a symbol number. Moreover, G is a matrix having N rowsand 2 columns, and may be a function of i. Moreover, G may be switchedat some given timing (i.e., may be a function of frequency or time).

Moreover, “processed signal 106A is transmitted from a plurality oftransmitting antennas and processed signal 106_B is also transmittedfrom a plurality of transmitting antennas” and “processed signal 106_Ais transmitted from a single transmitting antenna and processed signal106_B is also transmitted from a single transmitting antenna” may beswitched in the transmission device. Regarding the timing of theswitching, the switching may be performed per frame, and the switchingmay be performed in accordance with the decision to transmit a modulatedsignal (may be any arbitrary timing).

Note that at least one of the FPGA (Field Programmable Gate Array) andCPU (Central Processing Unit) may be configured to download, over awired or wireless connection, some or all of the software required toimplement the communications method described in the present disclosure.Furthermore, at least one of the FPGA (Field Programmable Gate Array)and CPU (Central Processing Unit) may be configured to download, over awired or wireless connection, some or all of the software required toperform updates. The downloaded software may be stored in a storage, andbased on the stored software, at least one of the FPGA and CPU may beoperated to implement the digital signal processing described in thepresent disclosure.

Here, a device including at least one of the FPGA and CPU may connect toa communications modem over a wired or wireless connect, and the deviceand communications modem may implement the communications methoddescribed in the present disclosure.

For example, a communications device such as the base station, AP, andterminal described in the present specification may include at least oneof the FPGA and the CPU, and include an interface for obtaining, from anexternal source, software for operating at least one of the FPGA and theCPU. The communications device may further include a storage for storingsoftware obtained from the external source, and implement the signalprocessing described in the present disclosure by operating the FPGA andCPU based on the stored software.

Although only some exemplary embodiments of the present disclosure havebeen described in detail above, those skilled in the art will readilyappreciate that many modifications are possible in the exemplaryembodiments without materially departing from the novel teachings andadvantages of the present disclosure. Accordingly, all suchmodifications are intended to be included within the scope of thepresent disclosure.

INDUSTRIAL APPLICABILITY

The present disclosure is applicable in radio communications systemsusing a single-carrier scheme and/or a multi-carrier scheme.

What is claimed is:
 1. A transmission method, comprising: generatingmodulated 16-quadrature amplitude modulation (QAM) points s1(i) by usingbits of a first stream and generating modulated quadrature phase shiftkeying (QPSK) points s2(i) by using bits of a second stream, where i isan integer greater than or equal to 0; converting the modulated 16-QAMpoints s1(i) to first converted points z1(i) and converting themodulated QPSK points s2(i) to second converted points z2(i), whereinconverting the modulated 16-QAM points s1(i) to the first convertedpoints z1(i) and converting the modulated QPSK points s2(i) to thesecond converted points z2(i) includes multiplying $\begin{matrix}{{\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}{by}\begin{pmatrix}\sqrt{4/3} & 0 \\0 & \sqrt{2/3}\end{pmatrix}};} & (i)\end{matrix}$ generating one or more signals that include the firstconverted points z1(i) and the second converted points z2(i); andtransmitting the one or more signals.
 2. The transmission method ofclaim 1, wherein the first converted points z1(i) and the secondconverted points z2(i) are defined as: ${\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\frac{1}{\sqrt{2}}\begin{pmatrix}1 & 1 \\1 & {- 1}\end{pmatrix}\begin{pmatrix}\sqrt{4/3} & 0 \\0 & \sqrt{2/3}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}},$ where y(i) is a function represented by e^(jδ(i))where δ(i) is a real value incremented by a constant value for every i.3. The transmission method of claim 2, wherein the constant value is2π/N.
 4. The transmission method of claim 2, wherein the one or moresignals comprise one or more orthogonal frequency division multiplexing(OFDM) symbols.
 5. The transmission method of claim 2, wherein thetransmission method is to be performed by a base station.
 6. Thetransmission method of claim 2, further comprising: receiving a controlsignal; selecting a precoding matrix from a plurality of precodingmatrixes based on the control signal; and performing a precoding basedon the precoding matrix.
 7. The transmission method of claim 2, furthercomprising: generating the first converted points z1(i) or the secondconverted points z2(i) based on one or more phase change values.
 8. Thetransmission method of claim 2, wherein a value of y(i) periodicallyvaries with a period of N, where N is
 8. 9. A device comprising: amapper to generate modulated 16-quadrature amplitude modulation (QAM)points s1(i) by using bits of a first stream, and to generate modulatedquadrature phase shift keying (QPSK) points s2(i) by using bits of asecond stream, where i is an integer greater than or equal to 0; asignal processor to convert the modulated 16-QAM points s1(i) to firstconverted points z1(i) and to convert the modulated QPSK points s2(i) tosecond converted points z2(i), wherein to convert the modulated 16-QAMpoints s1(i) to the first converted points z1(i) and to convert themodulated QPSK points s2(i) to the second converted points z2(i), thesignal processor is to multiply $\begin{matrix}{{\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}{by}\begin{pmatrix}\sqrt{4/3} & 0 \\0 & \sqrt{2/3}\end{pmatrix}};} & (i)\end{matrix}$ and a generator to generate one or more signals thatinclude the first converted points z1(i) and the second converted pointsz2(i).
 10. The device of claim 9, wherein the first converted pointsz1(i) and the second converted points z2(i) are defined as:${\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\frac{1}{\sqrt{2}}\begin{pmatrix}1 & 1 \\1 & {- 1}\end{pmatrix}\begin{pmatrix}\sqrt{4/3} & 0 \\0 & \sqrt{2/3}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}},$ where y(i) is a function represented by e^(jδ(i)) andδ(i) is a real value incremented by a constant value for every i. 11.The device of claim 10, wherein the constant value is 27π/ N.
 12. Thedevice of claim 10, further comprising: a transmitter to transmit theone or more signals.
 13. The device of claim 12, wherein the transmitteris to transmit the one or more signals via a plurality of antennas. 14.The device of claim 10, wherein the device comprises a base station. 15.The device of claim 10, wherein the signal processor is furtherconfigured to: receive a control signal; select a precoding matrix froma plurality of precoding matrixes based on the control signal; andperform a precoding based on the precoding matrix.
 16. The device ofclaim 10, wherein the signal processor is further configured to:generate the first converted points z1(i) or the second converted pointsz2(i) based on one or more phase change values.
 17. The device of claim10, wherein a value of y(i) periodically varies with a period of N,where N is
 8. 18. A reception method, comprising: obtaining one or morereception signals that include a first converted signal z1(i) and asecond converted signal z2(i), where i is an integer greater than orequal to 0, wherein the first converted signal z1(i) and the secondconverted signal z2(i) are generated by multiplying $\begin{matrix}{{\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}{by}\begin{pmatrix}\sqrt{4/3} & 0 \\0 & \sqrt{2/3}\end{pmatrix}},} & (i)\end{matrix}$ where s1(i) is modulated 16-quadrature amplitudemodulation (QAM) points and s2(i) is modulated quadrature phase shiftkeying (QPSK) points; and demodulating the first converted signal z1(i)according to a conversion applied to the modulated 16-QAM points s1(i)and demodulating the second converted signal z2(i) according to aconversion applied to the modulated QPSK points s2(i).
 19. The receptionmethod of claim 18, wherein the first converted signal z1(i) and thesecond converted signal z2(i) are defined as: ${\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\frac{1}{\sqrt{2}}\begin{pmatrix}1 & 1 \\1 & {- 1}\end{pmatrix}\begin{pmatrix}\sqrt{4/3} & 0 \\0 & \sqrt{2/3}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}},$ where y(i) is a function represented by e^(jδ(i)) andδ(i) is a real value incremented by a constant value for every i. 20.The reception method of claim 19, wherein the constant value is 2π/N.21. The reception method of claim 19, wherein the one more receptionsignals comprise orthogonal frequency division multiplexing (OFDM)symbols.
 22. The reception method of claim 19, wherein a value of y(i)periodically varies with a period of N, where N is
 8. 23. A receptiondevice, comprising: a receiver to receive one or more reception signalsthat include a first converted signal z1(i) and a second convertedsignal z2(i), where i is an integer greater than or equal to 0, whereinthe first converted signal z1(i) and the second converted signal z2(i)are generated by multiplying $\begin{matrix}{{\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}{by}\begin{pmatrix}\sqrt{4/3} & 0 \\0 & \sqrt{2/3}\end{pmatrix}},} & (i)\end{matrix}$ where s1(i) are modulated 16-quadrature amplitudemodulation (QAM) points and s2(i) are modulated quadrature phase shiftkeying (QPSK) points; and a demodulator to demodulate the firstconverted signal z1(i) according to a conversion applied to themodulated 16-QAM points s1(i) and demodulate the second converted signalz2(i) according to a conversion applied to the modulated QPSK pointss2(i).
 24. The reception device of claim 23, wherein the first convertedsignal z1(i) and the second converted signal z2(i) are defined as:${\begin{pmatrix}{z1(i)} \\{z2(i)}\end{pmatrix} = {\begin{pmatrix}1 & 0 \\0 & {y(i)}\end{pmatrix}\frac{1}{\sqrt{2}}\begin{pmatrix}1 & 1 \\1 & {- 1}\end{pmatrix}\begin{pmatrix}\sqrt{4/3} & 0 \\0 & \sqrt{2/3}\end{pmatrix}\begin{pmatrix}{s1(i)} \\{s2(i)}\end{pmatrix}}},$ where y(i) is a function represented by e^(jδ(i))where δ(i) is a real value incremented by a constant value for every i.25. The reception device of claim 24, wherein the constant value is2π/N.
 26. The reception device of claim 24, wherein the one or morereception signals comprise orthogonal frequency divisional multiplexing(OFDM) symbols.
 27. The reception device of claim 24, wherein a value ofy(i) periodically varies with a period of N, where N is 8.